From ac101b7cb17d4a5df1ab735420d0ee3593465dcf Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 23 Jun 2020 12:40:26 -0700 Subject: KVM: x86/mmu: Avoid multiple hash lookups in kvm_get_mmu_page() Refactor for_each_valid_sp() to take the list of shadow pages instead of retrieving it from a gfn to avoid doing the gfn->list hash and lookup multiple times during kvm_get_mmu_page(). Cc: Peter Feiner Cc: Jon Cargille Cc: Jim Mattson Signed-off-by: Sean Christopherson Message-Id: <20200623194027.23135-2-sean.j.christopherson@intel.com> Reviewed-By: Jon Cargille Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/mmu.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'arch/x86/kvm/mmu') diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 03ce2cad04f7..713371316848 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -2243,15 +2243,14 @@ static bool kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, static void kvm_mmu_commit_zap_page(struct kvm *kvm, struct list_head *invalid_list); - -#define for_each_valid_sp(_kvm, _sp, _gfn) \ - hlist_for_each_entry(_sp, \ - &(_kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(_gfn)], hash_link) \ +#define for_each_valid_sp(_kvm, _sp, _list) \ + hlist_for_each_entry(_sp, _list, hash_link) \ if (is_obsolete_sp((_kvm), (_sp))) { \ } else #define for_each_gfn_indirect_valid_sp(_kvm, _sp, _gfn) \ - for_each_valid_sp(_kvm, _sp, _gfn) \ + for_each_valid_sp(_kvm, _sp, \ + &(_kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(_gfn)]) \ if ((_sp)->gfn != (_gfn) || (_sp)->role.direct) {} else static inline bool is_ept_sp(struct kvm_mmu_page *sp) @@ -2462,6 +2461,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, unsigned int access) { union kvm_mmu_page_role role; + struct hlist_head *sp_list; unsigned quadrant; struct kvm_mmu_page *sp; bool need_sync = false; @@ -2481,7 +2481,9 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1; role.quadrant = quadrant; } - for_each_valid_sp(vcpu->kvm, sp, gfn) { + + sp_list = &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]; + for_each_valid_sp(vcpu->kvm, sp, sp_list) { if (sp->gfn != gfn) { collisions++; continue; @@ -2518,8 +2520,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, sp->gfn = gfn; sp->role = role; - hlist_add_head(&sp->hash_link, - &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]); + hlist_add_head(&sp->hash_link, sp_list); if (!direct) { /* * we should do write protection before syncing pages -- cgit v1.2.3