[RFC v2 PATCH 15/21] KVM: add tracepoint on enabling/disabling direct interrupt delivery

[Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>]

Add trace event "kvm_set_direct_interrupt" to trace enabling/disabling
direct interrupt delivery on slave CPUs. At the event, the guest rip and
whether the feature is enabled or not is logged.

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---

 arch/x86/kvm/trace.h |   18 ++++++++++++++++++
 arch/x86/kvm/vmx.c   |    2 ++
 arch/x86/kvm/x86.c   |    1 +
 3 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index a71faf7..6081be7 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -551,6 +551,24 @@ TRACE_EVENT(kvm_pv_eoi,
 	TP_printk("apicid %x vector %d", __entry->apicid, __entry->vector)
 );
 
+TRACE_EVENT(kvm_set_direct_interrupt,
+	TP_PROTO(struct kvm_vcpu *vcpu, bool enabled),
+	TP_ARGS(vcpu, enabled),
+
+	TP_STRUCT__entry(
+		__field(	unsigned long,	guest_rip	)
+		__field(	bool,	        enabled         )
+	),
+
+	TP_fast_assign(
+		__entry->guest_rip	= kvm_rip_read(vcpu);
+		__entry->enabled        = enabled;
+	),
+
+	TP_printk("rip 0x%lx enabled %d",
+		 __entry->guest_rip, __entry->enabled)
+);
+
 /*
  * Tracepoint for nested VMRUN
  */
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 605abea..6dc59c8 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1719,6 +1719,8 @@ static void vmx_set_direct_interrupt(struct kvm_vcpu *vcpu, bool enabled)
 	else
 		vmcs_set_bits(PIN_BASED_VM_EXEC_CONTROL,
 			      PIN_BASED_EXT_INTR_MASK);
+
+	trace_kvm_set_direct_interrupt(vcpu, enabled);
 }
 
 static void vmx_set_slave_mode(struct kvm_vcpu *vcpu, bool slave)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b7d28df..1449187 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6936,3 +6936,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intr_vmexit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_invlpga);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_skinit);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_intercepts);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_set_direct_interrupt);