1 files changed, 4 insertions, 0 deletions

diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
index 7ad503fbff74..3dc4ca1d6c08 100644
--- a/tools/perf/util/annotate.h
+++ b/tools/perf/util/annotate.h
@@ -202,6 +202,10 @@ struct cyc_hist {
 /** struct annotated_source - symbols with hits have this attached as in sannotation
  *
  * @histograms: Array of addr hit histograms per event being monitored
+ * nr_histograms: This may not be the same as evsel->evlist->nr_entries if
+ *                we have more than a group in a evlist, where we will want
+ *                to see each group separately, that is why symbol__annotate2()
+ *                sets src->nr_histograms to evsel->nr_members.
  * @lines: If 'print_lines' is specified, per source code line percentages
  * @source: source parsed from a disassembler like objdump -dS
  * @cyc_hist: Average cycles per basic block