[PATCH v3 02/19] KVM: MMU: do not update slot bitmap if spte is nonpresent

Xiao Guangrong
2011-06-30T08:17:51Z

Set slot bitmap only if the spte is present

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
arch/x86/kvm/mmu.c | 15 +++++++--------
1 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 03323dc..02c839f 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -743,9 +743,6 @@ static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
struct kvm_mmu_page *sp;
unsigned long *rmapp;

- if (!is_rmap_spte(*spte))
- return 0;
-
sp = page_header(__pa(spte));
kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn);
rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level);
@@ -2087,11 +2084,13 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
if (!was_rmapped && is_large_pte(*sptep))
++vcpu->kvm->stat.lpages;

- page_header_update_slot(vcpu->kvm, sptep, gfn);
- if (!was_rmapped) {
- rmap_count = rmap_add(vcpu, sptep, gfn);
- if (rmap_count > RMAP_RECYCLE_THRESHOLD)
- rmap_recycle(vcpu, sptep, gfn);
+ if (is_shadow_present_pte(*sptep)) {
+ page_header_update_slot(vcpu->kvm, sptep, gfn);
+ if (!was_rmapped) {
+ rmap_count = rmap_add(vcpu, sptep, gfn);
+ if (rmap_count > RMAP_RECYCLE_THRESHOLD)
+ rmap_recycle(vcpu, sptep, gfn);
+ }
}
kvm_release_pfn_clean(pfn);
if (speculative) {
--
1.7.5.4