KVM: x86/mmu: Bump pf_taken stat only in the "real" page fault handler

Account stat.pf_taken in kvm_mmu_page_fault(), i.e. the actual page fault
handler, instead of conditionally bumping it in kvm_mmu_do_page_fault().
The "real" page fault handler is the only path that should ever increment
the number of taken page faults, as all other paths that "do page fault"
are by definition not handling faults that occurred in the guest.

Signed-off-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 1432deb75cbb2eb5ce743551fde90ce9b0fa66e2..f42ad79a31574a40b57b47771e5eed5a2d501b57 100644 (file)
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5925,6 +5925,8 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err
        }
 
        if (r == RET_PF_INVALID) {
+               vcpu->stat.pf_taken++;
+
                r = kvm_mmu_do_page_fault(vcpu, cr2_or_gpa, error_code, false,
                                          &emulation_type);
                if (KVM_BUG_ON(r == RET_PF_INVALID, vcpu->kvm))

diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index ce2fcd19ba6be0ba0025f32bf57791254158efce..8efd31b3856b4a75d79adc0b9323af31eb896dc0 100644 (file)
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -318,14 +318,6 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
                fault.slot = kvm_vcpu_gfn_to_memslot(vcpu, fault.gfn);
        }
 
-       /*
-        * Async #PF "faults", a.k.a. prefetch faults, are not faults from the
-        * guest perspective and have already been counted at the time of the
-        * original fault.
-        */
-       if (!prefetch)
-               vcpu->stat.pf_taken++;
-
        if (IS_ENABLED(CONFIG_MITIGATION_RETPOLINE) && fault.is_tdp)
                r = kvm_tdp_page_fault(vcpu, &fault);
        else