diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index 514b06d..6e393c9 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -23,6 +23,7 @@
 	struct sample_queue	*sample_buffer;
 	struct sample_queue	*last_sample;
 	int			sample_buffer_idx;
+	unsigned int		nr_samples;
 };
 
 struct perf_session {