From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
This is just for convenience for benchmark.
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
arch/x86/kvm/vmx.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 08d13febc4b5..a4971b778794 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -10096,6 +10096,9 @@ static int (*const kvm_vmx_exit_handlers_fast[]) (struct kvm_vcpu *vcpu) = {
static const int kvm_vmx_max_exit_handlers_fast =
ARRAY_SIZE(kvm_vmx_exit_handlers_fast);
+static bool __ro_after_init enable_fast_exit_handler = true;
+module_param_named(fast_exit_handler, enable_fast_exit_handler, bool, 0444);
+static DEFINE_STATIC_KEY_TRUE(enable_fast_exit_handler_key);
static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
{
@@ -10370,7 +10373,8 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu)
vmx_complete_atomic_exit(vmx);
vmx_recover_nmi_blocking(vmx);
- if (!is_guest_mode(vcpu) &&
+ if (static_branch_likely(&enable_fast_exit_handler_key) &&
+ !is_guest_mode(vcpu) &&
vmx->exit_reason < kvm_vmx_max_exit_handlers_fast &&
kvm_vmx_exit_handlers_fast[vmx->exit_reason]) {
bool idtv_info_valid =
@@ -13291,6 +13295,11 @@ static int __init vmx_init(void)
{
int r;
+ if (enable_fast_exit_handler)
+ static_branch_enable(&enable_fast_exit_handler_key);
+ else
+ static_branch_disable(&enable_fast_exit_handler_key);
+
#if IS_ENABLED(CONFIG_HYPERV)
/*
* Enlightened VMCS usage should be recommended and the host needs
--
2.17.1
