From b9aec44eab2353c816488f1c0e2ab9fd0058266b Mon Sep 17 00:00:00 2001 From: David Matlack Date: Fri, 13 Aug 2021 20:35:03 +0000 Subject: [PATCH] KVM: x86/mmu: Avoid memslot lookup in rmap_add Avoid the memslot lookup in rmap_add, by passing it down from the fault handling code to mmu_set_spte and then to rmap_add. No functional change intended. Signed-off-by: David Matlack Message-Id: <20210813203504.2742757-6-dmatlack@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu/mmu.c | 27 +++++++-------------------- arch/x86/kvm/mmu/paging_tmpl.h | 12 +++++++++--- 2 files changed, 16 insertions(+), 23 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 4b304f60cf441..7ff2c6c896a8d 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1625,16 +1625,15 @@ static bool kvm_test_age_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head, #define RMAP_RECYCLE_THRESHOLD 1000 -static void rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) +static void rmap_add(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, + u64 *spte, gfn_t gfn) { - struct kvm_memory_slot *slot; struct kvm_mmu_page *sp; struct kvm_rmap_head *rmap_head; int rmap_count; sp = sptep_to_sp(spte); kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn); - slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); rmap_head = gfn_to_rmap(gfn, sp->role.level, slot); rmap_count = pte_list_add(vcpu, spte, rmap_head); @@ -2674,8 +2673,8 @@ int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync, return 0; } -static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, - unsigned int pte_access, gfn_t gfn, +static int mmu_set_spte(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot, + u64 *sptep, unsigned int pte_access, gfn_t gfn, kvm_pfn_t pfn, struct kvm_page_fault *fault) { struct kvm_mmu_page *sp = sptep_to_sp(sptep); @@ -2744,24 +2743,12 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, if (!was_rmapped) { WARN_ON_ONCE(ret == RET_PF_SPURIOUS); kvm_update_page_stats(vcpu->kvm, level, 1); - rmap_add(vcpu, sptep, gfn); + rmap_add(vcpu, slot, sptep, gfn); } return ret; } -static kvm_pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, - bool no_dirty_log) -{ - struct kvm_memory_slot *slot; - - slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log); - if (!slot) - return KVM_PFN_ERR_FAULT; - - return gfn_to_pfn_memslot_atomic(slot, gfn); -} - static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *start, u64 *end) @@ -2782,7 +2769,7 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, return -1; for (i = 0; i < ret; i++, gfn++, start++) { - mmu_set_spte(vcpu, start, access, gfn, + mmu_set_spte(vcpu, slot, start, access, gfn, page_to_pfn(pages[i]), NULL); put_page(pages[i]); } @@ -2984,7 +2971,7 @@ static int __direct_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) if (WARN_ON_ONCE(it.level != fault->goal_level)) return -EFAULT; - ret = mmu_set_spte(vcpu, it.sptep, ACC_ALL, + ret = mmu_set_spte(vcpu, fault->slot, it.sptep, ACC_ALL, base_gfn, fault->pfn, fault); if (ret == RET_PF_SPURIOUS) return ret; diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index 8c07c42a4d73d..44361f7e70c8e 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -561,6 +561,7 @@ static bool FNAME(prefetch_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *spte, pt_element_t gpte, bool no_dirty_log) { + struct kvm_memory_slot *slot; unsigned pte_access; gfn_t gfn; kvm_pfn_t pfn; @@ -573,12 +574,17 @@ FNAME(prefetch_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, gfn = gpte_to_gfn(gpte); pte_access = sp->role.access & FNAME(gpte_access)(gpte); FNAME(protect_clean_gpte)(vcpu->arch.mmu, &pte_access, gpte); - pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn, + + slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log && (pte_access & ACC_WRITE_MASK)); + if (!slot) + return false; + + pfn = gfn_to_pfn_memslot_atomic(slot, gfn); if (is_error_pfn(pfn)) return false; - mmu_set_spte(vcpu, spte, pte_access, gfn, pfn, NULL); + mmu_set_spte(vcpu, slot, spte, pte_access, gfn, pfn, NULL); kvm_release_pfn_clean(pfn); return true; } @@ -757,7 +763,7 @@ static int FNAME(fetch)(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault, if (WARN_ON_ONCE(it.level != fault->goal_level)) return -EFAULT; - ret = mmu_set_spte(vcpu, it.sptep, gw->pte_access, + ret = mmu_set_spte(vcpu, fault->slot, it.sptep, gw->pte_access, base_gfn, fault->pfn, fault); if (ret == RET_PF_SPURIOUS) return ret; -- 2.39.5