KVM: MMU: count used shadow pages on prepareing path
Move counting used shadow pages from commiting path to preparing path to
reduce tlb flush on some paths
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a62ba46..91d3069 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1039,7 +1039,7 @@
percpu_counter_add(&kvm_total_used_mmu_pages, nr);
}
-static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
+static void kvm_mmu_free_page(struct kvm_mmu_page *sp)
{
ASSERT(is_empty_shadow_page(sp->spt));
hlist_del(&sp->hash_link);
@@ -1048,7 +1048,6 @@
if (!sp->role.direct)
free_page((unsigned long)sp->gfns);
kmem_cache_free(mmu_page_header_cache, sp);
- kvm_mod_used_mmu_pages(kvm, -1);
}
static unsigned kvm_page_table_hashfn(gfn_t gfn)
@@ -1655,6 +1654,7 @@
/* Count self */
ret++;
list_move(&sp->link, invalid_list);
+ kvm_mod_used_mmu_pages(kvm, -1);
} else {
list_move(&sp->link, &kvm->arch.active_mmu_pages);
kvm_reload_remote_mmus(kvm);
@@ -1678,7 +1678,7 @@
do {
sp = list_first_entry(invalid_list, struct kvm_mmu_page, link);
WARN_ON(!sp->role.invalid || sp->root_count);
- kvm_mmu_free_page(kvm, sp);
+ kvm_mmu_free_page(sp);
} while (!list_empty(invalid_list));
}
@@ -1704,8 +1704,8 @@
page = container_of(kvm->arch.active_mmu_pages.prev,
struct kvm_mmu_page, link);
kvm_mmu_prepare_zap_page(kvm, page, &invalid_list);
- kvm_mmu_commit_zap_page(kvm, &invalid_list);
}
+ kvm_mmu_commit_zap_page(kvm, &invalid_list);
goal_nr_mmu_pages = kvm->arch.n_used_mmu_pages;
}
@@ -3302,9 +3302,9 @@
sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev,
struct kvm_mmu_page, link);
kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list);
- kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
++vcpu->kvm->stat.mmu_recycled;
}
+ kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list);
}
int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code,