On 10/12/20 09:15, Stephen Zhang wrote:
code changes in handle_io() to save some CPU cycles.
Signed-off-by: Stephen Zhang <starzhangzsd@xxxxxxxxx>
---
arch/x86/kvm/vmx/vmx.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 47b8357..109bcf64 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4899,15 +4899,14 @@ static int handle_triple_fault(struct kvm_vcpu *vcpu)
static int handle_io(struct kvm_vcpu *vcpu)
{
unsigned long exit_qualification;
- int size, in, string;
+ int size, in;
unsigned port;
exit_qualification = vmx_get_exit_qual(vcpu);
- string = (exit_qualification & 16) != 0;
++vcpu->stat.io_exits;
- if (string)
+ if (exit_qualification & 16)
return kvm_emulate_instruction(vcpu, 0);
port = exit_qualification >> 16;
I would be very surprised if there's any change in the assembly code
after this patch.
Paolo
