Attach struct kvm_mmu_pages to every page in the TDP MMU to track metadata, facilitate NX reclaim, and enable inproved parallelism of MMU operations in future patches. Tested by running kvm-unit-tests and KVM selftests on an Intel Haswell machine. This series introduced no new failures. This series can be viewed in Gerrit at: https://linux-review.googlesource.com/c/virt/kvm/kvm/+/2538 Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx> --- arch/x86/include/asm/kvm_host.h | 4 ++++ arch/x86/kvm/mmu/tdp_mmu.c | 13 ++++++++++--- 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 9ce6b35ecb33a..a76bcb51d43d8 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -972,7 +972,11 @@ struct kvm_arch { * operations. */ bool tdp_mmu_enabled; + + /* List of struct tdp_mmu_pages being used as roots */ struct list_head tdp_mmu_roots; + /* List of struct tdp_mmu_pages not being used as roots */ + struct list_head tdp_mmu_pages; }; struct kvm_vm_stat { diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index a3bcee6bf30e8..557e780bdf9f9 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -30,6 +30,7 @@ void kvm_mmu_init_tdp_mmu(struct kvm *kvm) kvm->arch.tdp_mmu_enabled = true; INIT_LIST_HEAD(&kvm->arch.tdp_mmu_roots); + INIT_LIST_HEAD(&kvm->arch.tdp_mmu_pages); } void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) @@ -244,6 +245,7 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn, bool is_leaf = is_present && is_last_spte(new_spte, level); bool pfn_changed = spte_to_pfn(old_spte) != spte_to_pfn(new_spte); u64 *pt; + struct kvm_mmu_page *sp; u64 old_child_spte; int i; @@ -309,6 +311,9 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn, */ if (was_present && !was_leaf && (pfn_changed || !is_present)) { pt = spte_to_child_pt(old_spte, level); + sp = sptep_to_sp(pt); + + list_del(&sp->link); for (i = 0; i < PT64_ENT_PER_PAGE; i++) { old_child_spte = *(pt + i); @@ -322,6 +327,7 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn, KVM_PAGES_PER_HPAGE(level)); free_page((unsigned long)pt); + kmem_cache_free(mmu_page_header_cache, sp); } } @@ -474,8 +480,7 @@ int kvm_tdp_mmu_page_fault(struct kvm_vcpu *vcpu, int write, int map_writable, bool prefault, bool account_disallowed_nx_lpage) { struct tdp_iter iter; - struct kvm_mmu_memory_cache *pf_pt_cache = - &vcpu->arch.mmu_shadow_page_cache; + struct kvm_mmu_page *sp; u64 *child_pt; u64 new_spte; int ret; @@ -520,7 +525,9 @@ int kvm_tdp_mmu_page_fault(struct kvm_vcpu *vcpu, int write, int map_writable, } if (!is_shadow_present_pte(iter.old_spte)) { - child_pt = kvm_mmu_memory_cache_alloc(pf_pt_cache); + sp = alloc_tdp_mmu_page(vcpu, iter.gfn, iter.level); + list_add(&sp->link, &vcpu->kvm->arch.tdp_mmu_pages); + child_pt = sp->spt; clear_page(child_pt); new_spte = make_nonleaf_spte(child_pt, !shadow_accessed_mask); -- 2.28.0.709.gb0816b6eb0-goog
