From 5ed5c5c8fdbab889837c9223fc6f4bdaa830879c Mon Sep 17 00:00:00 2001 From: Takuya Yoshikawa Date: Fri, 16 Oct 2015 17:05:13 +0900 Subject: [PATCH] KVM: x86: MMU: Simplify force_pt_level calculation code in FNAME(page_fault)() As a bonus, an extra memory slot search can be eliminated when is_self_change_mapping is true. Signed-off-by: Takuya Yoshikawa Signed-off-by: Paolo Bonzini --- arch/x86/kvm/paging_tmpl.h | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 07f1a4e..8ebc3a5 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -743,15 +743,14 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, is_self_change_mapping = FNAME(is_self_change_mapping)(vcpu, &walker, user_fault, &vcpu->arch.write_fault_to_shadow_pgtable); - if (walker.level >= PT_DIRECTORY_LEVEL) - force_pt_level = mapping_level_dirty_bitmap(vcpu, walker.gfn) - || is_self_change_mapping; - else + if (walker.level >= PT_DIRECTORY_LEVEL && !is_self_change_mapping) { + force_pt_level = mapping_level_dirty_bitmap(vcpu, walker.gfn); + if (!force_pt_level) { + level = min(walker.level, mapping_level(vcpu, walker.gfn)); + walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1); + } + } else force_pt_level = true; - if (!force_pt_level) { - level = min(walker.level, mapping_level(vcpu, walker.gfn)); - walker.gfn = walker.gfn & ~(KVM_PAGES_PER_HPAGE(level) - 1); - } mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); -- 2.7.4