diff options
| author | Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> | 2010-07-16 11:27:10 +0800 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2010-08-02 06:40:59 +0300 |
| commit | be233d49ea8c1fde9f4afec378dc2c2f16ab0263 (patch) | |
| tree | d595b2ea6f153b8e489fd78cdf3bca7ae015abca /arch | |
| parent | 9ed5520dd3c9cb79c25f95fce9c57b87637d0fb7 (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.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a04756a26fe..9c7fae08291 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))); |