KVM: x86/mmu: Always use current mmu's role when loading new PGD

Since the guest PGD is now loaded after the MMU has been set up
completely, the desired role for a cache hit is simply the current
mmu_role.  There is no need to compute it again, so __kvm_mmu_new_pgd
can be folded in kvm_mmu_new_pgd.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 8464cd6..a1768a8 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -181,8 +181,6 @@ struct kmem_cache *mmu_page_header_cache;
 static struct percpu_counter kvm_total_used_mmu_pages;
 
 static void mmu_spte_set(u64 *sptep, u64 spte);
-static union kvm_mmu_page_role
-kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu);
 
 struct kvm_mmu_role_regs {
        const unsigned long cr0;
@@ -4169,10 +4167,10 @@ static bool fast_pgd_switch(struct kvm *kvm, struct kvm_mmu *mmu,
                return cached_root_find_without_current(kvm, mmu, new_pgd, new_role);
 }
 
-static void __kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd,
-                             union kvm_mmu_page_role new_role)
+void kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd)
 {
        struct kvm_mmu *mmu = vcpu->arch.mmu;
+       union kvm_mmu_page_role new_role = mmu->mmu_role.base;
 
        if (!fast_pgd_switch(vcpu->kvm, mmu, new_pgd, new_role)) {
                /* kvm_mmu_ensure_valid_pgd will set up a new root.  */
@@ -4208,11 +4206,6 @@ static void __kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd,
                __clear_sp_write_flooding_count(
                                to_shadow_page(vcpu->arch.mmu->root.hpa));
 }
-
-void kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd)
-{
-       __kvm_mmu_new_pgd(vcpu, new_pgd, kvm_mmu_calc_root_page_role(vcpu));
-}
 EXPORT_SYMBOL_GPL(kvm_mmu_new_pgd);
 
 static unsigned long get_cr3(struct kvm_vcpu *vcpu)
@@ -4882,7 +4875,7 @@ void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr0,
        new_role = kvm_calc_shadow_npt_root_page_role(vcpu, &regs);
 
        shadow_mmu_init_context(vcpu, context, &regs, new_role);
-       __kvm_mmu_new_pgd(vcpu, nested_cr3, new_role.base);
+       kvm_mmu_new_pgd(vcpu, nested_cr3);
 }
 EXPORT_SYMBOL_GPL(kvm_init_shadow_npt_mmu);
 
@@ -4938,7 +4931,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly,
                reset_ept_shadow_zero_bits_mask(context, execonly);
        }
 
-       __kvm_mmu_new_pgd(vcpu, new_eptp, new_role.base);
+       kvm_mmu_new_pgd(vcpu, new_eptp);
 }
 EXPORT_SYMBOL_GPL(kvm_init_shadow_ept_mmu);
 
@@ -5023,20 +5016,6 @@ void kvm_init_mmu(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL_GPL(kvm_init_mmu);
 
-static union kvm_mmu_page_role
-kvm_mmu_calc_root_page_role(struct kvm_vcpu *vcpu)
-{
-       struct kvm_mmu_role_regs regs = vcpu_to_role_regs(vcpu);
-       union kvm_mmu_role role;
-
-       if (tdp_enabled)
-               role = kvm_calc_tdp_mmu_root_page_role(vcpu, &regs, true);
-       else
-               role = kvm_calc_shadow_mmu_root_page_role(vcpu, &regs, true);
-
-       return role.base;
-}
-
 void kvm_mmu_after_set_cpuid(struct kvm_vcpu *vcpu)
 {
        /*