summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
authorXiao Guangrong <xiaoguangrong@cn.fujitsu.com>2010-07-16 11:27:10 +0800
committerAvi Kivity <avi@redhat.com>2010-08-02 06:40:59 +0300
commitbe233d49ea8c1fde9f4afec378dc2c2f16ab0263 (patch)
treed595b2ea6f153b8e489fd78cdf3bca7ae015abca /arch
parent9ed5520dd3c9cb79c25f95fce9c57b87637d0fb7 (diff)
KVM: MMU: don't atomicly set spte if it's not present
If the old mapping is not present, the spte.a is not lost, so no need atomic operation to set it Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kvm/mmu.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a04756a26fe2..9c7fae08291d 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -307,9 +307,10 @@ static void update_spte(u64 *sptep, u64 new_spte)
{
u64 old_spte;
- if (!shadow_accessed_mask || (new_spte & shadow_accessed_mask)) {
+ if (!shadow_accessed_mask || (new_spte & shadow_accessed_mask) ||
+ !is_rmap_spte(*sptep))
__set_spte(sptep, new_spte);
- } else {
+ else {
old_spte = __xchg_spte(sptep, new_spte);
if (old_spte & shadow_accessed_mask)
mark_page_accessed(pfn_to_page(spte_to_pfn(old_spte)));