[PATCH bpf v4 2/2] selftest/bpf: Add map_in_maps with BPF_MAP_TYPE_PERF_EVENT_ARRAY values

[Andrey Grafin <conquistador@xxxxxxxxxxxxxx>]

Check that bpf_object__load() successfully creates map_in_maps
with BPF_MAP_TYPE_PERF_EVENT_ARRAY values.
This changes cover fix in the commit 912884275669
("libbpf: Apply map_set_def_max_entries() for inner_maps on creation").

A command line output is:
- w/o fix
$ sudo ./test_maps
libbpf: map 'mim_array_pe': failed to create inner map: -22
libbpf: map 'mim_array_pe': failed to create: Invalid argument(-22)
libbpf: failed to load object './test_map_in_map.bpf.o'
Failed to load test prog

- with fix
$ sudo ./test_maps
...
test_maps: OK, 0 SKIPPED

Signed-off-by: Andrey Grafin <conquistador@xxxxxxxxxxxxxx>
---
 .../selftests/bpf/progs/test_map_in_map.c     | 23 +++++++++++++++++++
 tools/testing/selftests/bpf/test_maps.c       |  6 ++++-
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/progs/test_map_in_map.c b/tools/testing/selftests/bpf/progs/test_map_in_map.c
index f416032ba858..54ce1f4bdc7b 100644
--- a/tools/testing/selftests/bpf/progs/test_map_in_map.c
+++ b/tools/testing/selftests/bpf/progs/test_map_in_map.c
@@ -21,6 +21,29 @@ struct {
 	__type(value, __u32);
 } mim_hash SEC(".maps");
 
+struct perf_event_array {
+	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
+	__type(key, __u32);
+	__type(value, __u32);
+} inner_map0 SEC(".maps"), inner_map1 SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
+	__uint(max_entries, 2);
+	__type(key, __u32);
+	__array(values, struct perf_event_array);
+} mim_array_pe SEC(".maps") = {
+	.values = {&inner_map0, &inner_map1}};
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH_OF_MAPS);
+	__uint(max_entries, 1);
+	__type(key, __u32);
+	__array(values, struct perf_event_array);
+} mim_hash_pe SEC(".maps") = {
+	.values = {&inner_map0}};
+
+
 SEC("xdp")
 int xdp_mimtest0(struct xdp_md *ctx)
 {
diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index 7fc00e423e4d..e0dd101c9f2b 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -1190,7 +1190,11 @@ static void test_map_in_map(void)
 		goto out_map_in_map;
 	}
 
-	bpf_object__load(obj);
+	err = bpf_object__load(obj);
+	if (err) {
+		printf("Failed to load test prog\n");
+		goto out_map_in_map;
+	}
 
 	map = bpf_object__find_map_by_name(obj, "mim_array");
 	if (!map) {
-- 
2.41.0