KVM: SVM: Add kvm_nested_intercepts tracepoint

This patch adds a tracepoint to get information about the
most important intercept bitmasks from the nested vmcb.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/svm.c

@@ -1845,6 +1845,11 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 			       nested_vmcb->control.event_inj,
 			       nested_vmcb->control.nested_ctl);
 
+	trace_kvm_nested_intercepts(nested_vmcb->control.intercept_cr_read,
+				    nested_vmcb->control.intercept_cr_write,
+				    nested_vmcb->control.intercept_exceptions,
+				    nested_vmcb->control.intercept);
+
 	/* Clear internal status */
 	kvm_clear_exception_queue(&svm->vcpu);
 	kvm_clear_interrupt_queue(&svm->vcpu);

arch/x86/kvm/trace.h

@@ -419,6 +419,28 @@ TRACE_EVENT(kvm_nested_vmrun,
 		__entry->npt ? "on" : "off")
 );
 
+TRACE_EVENT(kvm_nested_intercepts,
+	    TP_PROTO(__u16 cr_read, __u16 cr_write, __u32 exceptions, __u64 intercept),
+	    TP_ARGS(cr_read, cr_write, exceptions, intercept),
+
+	TP_STRUCT__entry(
+		__field(	__u16,		cr_read		)
+		__field(	__u16,		cr_write	)
+		__field(	__u32,		exceptions	)
+		__field(	__u64,		intercept	)
+	),
+
+	TP_fast_assign(
+		__entry->cr_read	= cr_read;
+		__entry->cr_write	= cr_write;
+		__entry->exceptions	= exceptions;
+		__entry->intercept	= intercept;
+	),
+
+	TP_printk("cr_read: %04x cr_write: %04x excp: %08x intercept: %016llx",
+		__entry->cr_read, __entry->cr_write, __entry->exceptions,
+		__entry->intercept)
+);
 /*
  * Tracepoint for #VMEXIT while nested
  */

arch/x86/kvm/x86.c

@@ -5909,3 +5909,4 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_nested_vmexit_inject);
 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);