[PATCH V3 3/3] kvm: add tracepoint for fast mmio

[Jason Wang <jasowang@redhat.com>]

Cc: Gleb Natapov <gleb@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 arch/x86/kvm/trace.h | 17 +++++++++++++++++
 arch/x86/kvm/vmx.c   |  1 +
 arch/x86/kvm/x86.c   |  1 +
 3 files changed, 19 insertions(+)

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 4eae7c3..2d4e81a 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -128,6 +128,23 @@ TRACE_EVENT(kvm_pio,
 		  __entry->count > 1 ? "(...)" : "")
 );
 
+TRACE_EVENT(kvm_fast_mmio,
+	TP_PROTO(u64 gpa),
+	TP_ARGS(gpa),
+
+	TP_STRUCT__entry(
+		__field(u64,	gpa)
+	),
+
+	TP_fast_assign(
+		__entry->gpa		= gpa;
+	),
+
+	TP_printk("fast mmio at gpa 0x%llx", __entry->gpa)
+);
+
+
+
 /*
  * Tracepoint for cpuid.
  */
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 83b7b5c..a55d279 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5831,6 +5831,7 @@ static int handle_ept_misconfig(struct kvm_vcpu *vcpu)
 	gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS);
 	if (!kvm_io_bus_write(vcpu, KVM_FAST_MMIO_BUS, gpa, 0, NULL)) {
 		skip_emulated_instruction(vcpu);
+		trace_kvm_fast_mmio(gpa);
 		return 1;
 	}
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8f0f6ec..36cf78e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8254,6 +8254,7 @@ bool kvm_arch_has_noncoherent_dma(struct kvm *kvm)
 EXPORT_SYMBOL_GPL(kvm_arch_has_noncoherent_dma);
 
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_exit);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_fast_mmio);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_inj_virq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_page_fault);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_msr);
-- 
2.1.4