KVM: Fix mmu shrinker error
kvm_mmu_remove_one_alloc_mmu_page() assumes kvm_mmu_zap_page() only reclaims
only one sp, but that's not the case. This will cause mmu shrinker returns
a wrong number. This patch fix the counting error.
Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 9696d65..18d2f58 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2902,13 +2902,13 @@
kvm_flush_remote_tlbs(kvm);
}
-static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm)
+static int kvm_mmu_remove_some_alloc_mmu_pages(struct kvm *kvm)
{
struct kvm_mmu_page *page;
page = container_of(kvm->arch.active_mmu_pages.prev,
struct kvm_mmu_page, link);
- kvm_mmu_zap_page(kvm, page);
+ return kvm_mmu_zap_page(kvm, page) + 1;
}
static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask)
@@ -2920,7 +2920,7 @@
spin_lock(&kvm_lock);
list_for_each_entry(kvm, &vm_list, vm_list) {
- int npages, idx;
+ int npages, idx, freed_pages;
idx = srcu_read_lock(&kvm->srcu);
spin_lock(&kvm->mmu_lock);
@@ -2928,8 +2928,8 @@
kvm->arch.n_free_mmu_pages;
cache_count += npages;
if (!kvm_freed && nr_to_scan > 0 && npages > 0) {
- kvm_mmu_remove_one_alloc_mmu_page(kvm);
- cache_count--;
+ freed_pages = kvm_mmu_remove_some_alloc_mmu_pages(kvm);
+ cache_count -= freed_pages;
kvm_freed = kvm;
}
nr_to_scan--;