1 files changed, 49 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c b/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c
new file mode 100644
index 000000000000..f7ee8fa377ad
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/btf_map_in_map.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+
+#include <test_progs.h>
+
+#include "test_btf_map_in_map.skel.h"
+
+void test_btf_map_in_map(void)
+{
+	int duration = 0, err, key = 0, val;
+	struct test_btf_map_in_map* skel;
+
+	skel = test_btf_map_in_map__open_and_load();
+	if (CHECK(!skel, "skel_open", "failed to open&load skeleton\n"))
+		return;
+
+	err = test_btf_map_in_map__attach(skel);
+	if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
+		goto cleanup;
+
+	/* inner1 = input, inner2 = input + 1 */
+	val = bpf_map__fd(skel->maps.inner_map1);
+	bpf_map_update_elem(bpf_map__fd(skel->maps.outer_arr), &key, &val, 0);
+	val = bpf_map__fd(skel->maps.inner_map2);
+	bpf_map_update_elem(bpf_map__fd(skel->maps.outer_hash), &key, &val, 0);
+	skel->bss->input = 1;
+	usleep(1);
+
+	bpf_map_lookup_elem(bpf_map__fd(skel->maps.inner_map1), &key, &val);
+	CHECK(val != 1, "inner1", "got %d != exp %d\n", val, 1);
+	bpf_map_lookup_elem(bpf_map__fd(skel->maps.inner_map2), &key, &val);
+	CHECK(val != 2, "inner2", "got %d != exp %d\n", val, 2);
+
+	/* inner1 = input + 1, inner2 = input */
+	val = bpf_map__fd(skel->maps.inner_map2);
+	bpf_map_update_elem(bpf_map__fd(skel->maps.outer_arr), &key, &val, 0);
+	val = bpf_map__fd(skel->maps.inner_map1);
+	bpf_map_update_elem(bpf_map__fd(skel->maps.outer_hash), &key, &val, 0);
+	skel->bss->input = 3;
+	usleep(1);
+
+	bpf_map_lookup_elem(bpf_map__fd(skel->maps.inner_map1), &key, &val);
+	CHECK(val != 4, "inner1", "got %d != exp %d\n", val, 4);
+	bpf_map_lookup_elem(bpf_map__fd(skel->maps.inner_map2), &key, &val);
+	CHECK(val != 3, "inner2", "got %d != exp %d\n", val, 3);
+
+cleanup:
+	test_btf_map_in_map__destroy(skel);
+}