KVM: x86: use guest_exit_irqoff
This gains a few clock cycles per vmexit. On Intel there is no need
anymore to enable the interrupts in vmx_handle_external_intr, since
we are using the "acknowledge interrupt on exit" feature. AMD
needs to do that, and must be careful to avoid the interrupt shadow.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 618463a..0cc6cf8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6709,16 +6709,9 @@
++vcpu->stat.exits;
- /*
- * We must have an instruction between local_irq_enable() and
- * kvm_guest_exit(), so the timer interrupt isn't delayed by
- * the interrupt shadow. The stat.exits increment will do nicely.
- * But we need to prevent reordering, hence this barrier():
- */
- barrier();
+ guest_exit_irqoff();
- guest_exit();
-
+ local_irq_enable();
preempt_enable();
vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);