From 05da45583de9b383dc81dd695fe248431d6c9f2b Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Sat, 23 Feb 2008 11:44:30 -0300 Subject: KVM: MMU: large page support Create large pages mappings if the guest PTE's are marked as such and the underlying memory is hugetlbfs backed. If the largepage contains write-protected pages, a large pte is not used. Gives a consistent 2% improvement for data copies on ram mounted filesystem, without NPT/EPT. Anthony measures a 4% improvement on 4-way kernbench, with NPT. Signed-off-by: Marcelo Tosatti Signed-off-by: Avi Kivity --- include/asm-x86/kvm_host.h | 9 +++++++++ include/linux/kvm_host.h | 5 +++++ 2 files changed, 14 insertions(+) (limited to 'include') diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h index 8c3f74b7352..95473ef5a90 100644 --- a/include/asm-x86/kvm_host.h +++ b/include/asm-x86/kvm_host.h @@ -39,6 +39,13 @@ #define INVALID_PAGE (~(hpa_t)0) #define UNMAPPED_GVA (~(gpa_t)0) +/* shadow tables are PAE even on non-PAE hosts */ +#define KVM_HPAGE_SHIFT 21 +#define KVM_HPAGE_SIZE (1UL << KVM_HPAGE_SHIFT) +#define KVM_HPAGE_MASK (~(KVM_HPAGE_SIZE - 1)) + +#define KVM_PAGES_PER_HPAGE (KVM_HPAGE_SIZE / PAGE_SIZE) + #define DE_VECTOR 0 #define UD_VECTOR 6 #define NM_VECTOR 7 @@ -230,6 +237,7 @@ struct kvm_vcpu_arch { struct { gfn_t gfn; /* presumed gfn during guest pte update */ struct page *page; /* page corresponding to that gfn */ + int largepage; } update_pte; struct i387_fxsave_struct host_fx_image; @@ -307,6 +315,7 @@ struct kvm_vm_stat { u32 mmu_recycled; u32 mmu_cache_miss; u32 remote_tlb_flush; + u32 lpages; }; struct kvm_vcpu_stat { diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 994278fb588..9750bb3c5a7 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -103,6 +103,10 @@ struct kvm_memory_slot { unsigned long flags; unsigned long *rmap; unsigned long *dirty_bitmap; + struct { + unsigned long rmap_pde; + int write_count; + } *lpage_info; unsigned long userspace_addr; int user_alloc; }; @@ -169,6 +173,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm, int user_alloc); gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn); struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); +unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn); void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page); int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, -- cgit v1.2.3