From e0df7b9f6cee43c01d6f4a8491bccfd410cb86e1 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Thu, 19 Aug 2010 18:11:05 -0700 Subject: [PATCH] KVM: abstract kvm x86 mmu->n_free_mmu_pages "free" is a poor name for this value. In this context, it means, "the number of mmu pages which this kvm instance should be able to allocate." But "free" implies much more that the objects are there and ready for use. "available" is a much better description, especially when you see how it is calculated. In this patch, we abstract its use into a function. We'll soon replace the function's contents by calculating the value in a different way. All of the reads of n_free_mmu_pages are taken care of in this patch. The modification sites will be handled in a patch later in the series. Signed-off-by: Dave Hansen Signed-off-by: Tim Pepper Signed-off-by: Avi Kivity --- arch/x86/kvm/mmu.c | 11 ++++------- arch/x86/kvm/mmu.h | 7 ++++++- 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index ff95d418750d..625b17894661 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1696,7 +1696,7 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages) int used_pages; LIST_HEAD(invalid_list); - used_pages = kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages; + used_pages = kvm->arch.n_alloc_mmu_pages - kvm_mmu_available_pages(kvm); used_pages = max(0, used_pages); /* @@ -2959,18 +2959,15 @@ EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt); void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) { - int free_pages; LIST_HEAD(invalid_list); - free_pages = vcpu->kvm->arch.n_free_mmu_pages; - while (free_pages < KVM_REFILL_PAGES && + while (kvm_mmu_available_pages(vcpu->kvm) < KVM_REFILL_PAGES && !list_empty(&vcpu->kvm->arch.active_mmu_pages)) { struct kvm_mmu_page *sp; sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev, struct kvm_mmu_page, link); - free_pages += kvm_mmu_prepare_zap_page(vcpu->kvm, sp, - &invalid_list); + kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list); ++vcpu->kvm->stat.mmu_recycled; } kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); @@ -3145,7 +3142,7 @@ static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); npages = kvm->arch.n_alloc_mmu_pages - - kvm->arch.n_free_mmu_pages; + kvm_mmu_available_pages(kvm); cache_count += npages; if (!kvm_freed && nr_to_scan > 0 && npages > 0) { freed_pages = kvm_mmu_remove_some_alloc_mmu_pages(kvm, diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index be66759321a5..c3a689ae7df0 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -50,9 +50,14 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]); +static inline unsigned int kvm_mmu_available_pages(struct kvm *kvm) +{ + return kvm->arch.n_free_mmu_pages; +} + static inline void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) { - if (unlikely(vcpu->kvm->arch.n_free_mmu_pages < KVM_MIN_FREE_MMU_PAGES)) + if (unlikely(kvm_mmu_available_pages(vcpu->kvm)< KVM_MIN_FREE_MMU_PAGES)) __kvm_mmu_free_some_pages(vcpu); }