From 51fb60d81b483ae75614d401e7d4271884894113 Mon Sep 17 00:00:00 2001 From: Gui Jianfeng Date: Fri, 16 Apr 2010 17:16:40 +0800 Subject: KVM: MMU: Move sync_page() first pte address calculation out of loop Move first pte address calculation out of loop to save some cycles. Signed-off-by: Gui Jianfeng Signed-off-by: Avi Kivity --- arch/x86/kvm/paging_tmpl.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index d9dea288e51d..5910557b3f33 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -572,12 +572,15 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) { int i, offset, nr_present; bool reset_host_protection; + gpa_t first_pte_gpa; offset = nr_present = 0; if (PTTYPE == 32) offset = sp->role.quadrant << PT64_LEVEL_BITS; + first_pte_gpa = gfn_to_gpa(sp->gfn) + offset * sizeof(pt_element_t); + for (i = 0; i < PT64_ENT_PER_PAGE; i++) { unsigned pte_access; pt_element_t gpte; @@ -587,8 +590,7 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) if (!is_shadow_present_pte(sp->spt[i])) continue; - pte_gpa = gfn_to_gpa(sp->gfn); - pte_gpa += (i+offset) * sizeof(pt_element_t); + pte_gpa = first_pte_gpa + i * sizeof(pt_element_t); if (kvm_read_guest_atomic(vcpu->kvm, pte_gpa, &gpte, sizeof(pt_element_t))) -- cgit v1.2.3