KVM: MMU: delay flush all tlbs on sync_page path

Quote from Avi:
| I don't think we need to flush immediately; set a "tlb dirty" bit somewhere
| that is cleareded when we flush the tlb.  kvm_mmu_notifier_invalidate_page()
| can consult the bit and force a flush if set.

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index da0794f707f6..ac4e83a1a10d 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -254,6 +254,7 @@ struct kvm {
         struct mmu_notifier mmu_notifier;
         unsigned long mmu_notifier_seq;
         long mmu_notifier_count;
+        long tlbs_dirty;
 #endif
 };
 
@@ -382,6 +383,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu);
 void kvm_resched(struct kvm_vcpu *vcpu);
 void kvm_load_guest_fpu(struct kvm_vcpu *vcpu);
 void kvm_put_guest_fpu(struct kvm_vcpu *vcpu);
+
 void kvm_flush_remote_tlbs(struct kvm *kvm);
 void kvm_reload_remote_mmus(struct kvm *kvm);