KVM: Trace mmio

Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/x86.c

@@ -37,6 +37,8 @@
 #include <linux/iommu.h>
 #include <linux/intel-iommu.h>
 #include <linux/cpufreq.h>
+#include <trace/events/kvm.h>
+#undef TRACE_INCLUDE_FILE
 #define CREATE_TRACE_POINTS
 #include "trace.h"
 
@@ -2425,6 +2427,8 @@ static int emulator_read_emulated(unsigned long addr,
 
 	if (vcpu->mmio_read_completed) {
 		memcpy(val, vcpu->mmio_data, bytes);
+		trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes,
+			       vcpu->mmio_phys_addr, *(u64 *)val);
 		vcpu->mmio_read_completed = 0;
 		return X86EMUL_CONTINUE;
 	}
@@ -2445,8 +2449,12 @@ mmio:
 	/*
 	 * Is this MMIO handled locally?
 	 */
-	if (!vcpu_mmio_read(vcpu, gpa, bytes, val))
+	if (!vcpu_mmio_read(vcpu, gpa, bytes, val)) {
+		trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes, gpa, *(u64 *)val);
 		return X86EMUL_CONTINUE;
+	}
+
+	trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, 0);
 
 	vcpu->mmio_needed = 1;
 	vcpu->mmio_phys_addr = gpa;
@@ -2490,6 +2498,7 @@ static int emulator_write_emulated_onepage(unsigned long addr,
 		return X86EMUL_CONTINUE;
 
 mmio:
+	trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, *(u64 *)val);
 	/*
 	 * Is this MMIO handled locally?
 	 */

include/trace/events/kvm.h

@@ -56,6 +56,39 @@ TRACE_EVENT(kvm_ack_irq,
 
 
 #endif /* defined(__KVM_HAVE_IOAPIC) */
+
+#define KVM_TRACE_MMIO_READ_UNSATISFIED 0
+#define KVM_TRACE_MMIO_READ 1
+#define KVM_TRACE_MMIO_WRITE 2
+
+#define kvm_trace_symbol_mmio \
+	{ KVM_TRACE_MMIO_READ_UNSATISFIED, "unsatisfied-read" }, \
+	{ KVM_TRACE_MMIO_READ, "read" }, \
+	{ KVM_TRACE_MMIO_WRITE, "write" }
+
+TRACE_EVENT(kvm_mmio,
+	TP_PROTO(int type, int len, u64 gpa, u64 val),
+	TP_ARGS(type, len, gpa, val),
+
+	TP_STRUCT__entry(
+		__field(	u32,	type		)
+		__field(	u32,	len		)
+		__field(	u64,	gpa		)
+		__field(	u64,	val		)
+	),
+
+	TP_fast_assign(
+		__entry->type		= type;
+		__entry->len		= len;
+		__entry->gpa		= gpa;
+		__entry->val		= val;
+	),
+
+	TP_printk("mmio %s len %u gpa 0x%llx val 0x%llx",
+		  __print_symbolic(__entry->type, kvm_trace_symbol_mmio),
+		  __entry->len, __entry->gpa, __entry->val)
+);
+
 #endif /* _TRACE_KVM_MAIN_H */
 
 /* This part must be outside protection */