[PATCH] perf test sample-parsing: Validate PERF_FORMAT_GROUP values without LOST

[PVS Narasimha Rao <venkatasuryapala@gmail.com>]

The sample parsing test only validates grouped read values
when PERF_FORMAT_LOST is present.

For PERF_FORMAT_GROUP without PERF_FORMAT_LOST, the contents of
read.group.values[] are not validated, allowing corruption of
parsed value and id fields to go undetected.

Validate value and id for grouped reads and continue to
validate lost when PERF_FORMAT_LOST is present.

Use next_sample_read_value() to walk the variable-sized group
entries.

Signed-off-by: PVS Narasimha Rao <venkatasuryapala@gmail.com>

diff --git a/tools/perf/tests/sample-parsing.c b/tools/perf/tests/sample-parsing.c
index 55f0b73ca20e..e44b01e5cd14 100644
--- a/tools/perf/tests/sample-parsing.c
+++ b/tools/perf/tests/sample-parsing.c
@@ -86,10 +86,27 @@ static bool samples_same(struct perf_sample *s1,
 			COMP(read.time_running);
 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
 		if (read_format & PERF_FORMAT_GROUP) {
+			struct sample_read_value *v1 = s1->read.group.values;
+			struct sample_read_value *v2 = s2->read.group.values;
+
 			for (i = 0; i < s1->read.group.nr; i++) {
-				/* FIXME: check values without LOST */
-				if (read_format & PERF_FORMAT_LOST)
-					MCOMP(read.group.values[i]);
+				if (v1->value != v2->value) {
+					pr_debug("Samples differ at 'read.group.values[].value'\n");
+					return false;
+				}
+
+				if (v1->id != v2->id) {
+					pr_debug("Samples differ at 'read.group.values[].id'\n");
+					return false;
+				}
+
+				if (read_format & PERF_FORMAT_LOST &&
+				    v1->lost != v2->lost) {
+					pr_debug("Samples differ at 'read.group.values[].lost'\n");
+					return false;
+				}
+				v1 = next_sample_read_value(v1, read_format);
+				v2 = next_sample_read_value(v2, read_format);
 			}
 		} else {
 			COMP(read.one.id);
-- 
2.43.7