1 files changed, 58 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/fentry_test.c b/tools/testing/selftests/bpf/prog_tests/fentry_test.c
new file mode 100644
index 000000000..c0d1d61d5
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/fentry_test.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Facebook */
+#include <test_progs.h>
+#include "fentry_test.lskel.h"
+
+static int fentry_test(struct fentry_test_lskel *fentry_skel)
+{
+	int err, prog_fd, i;
+	int link_fd;
+	__u64 *result;
+	LIBBPF_OPTS(bpf_test_run_opts, topts);
+
+	err = fentry_test_lskel__attach(fentry_skel);
+	if (!ASSERT_OK(err, "fentry_attach"))
+		return err;
+
+	/* Check that already linked program can't be attached again. */
+	link_fd = fentry_test_lskel__test1__attach(fentry_skel);
+	if (!ASSERT_LT(link_fd, 0, "fentry_attach_link"))
+		return -1;
+
+	prog_fd = fentry_skel->progs.test1.prog_fd;
+	err = bpf_prog_test_run_opts(prog_fd, &topts);
+	ASSERT_OK(err, "test_run");
+	ASSERT_EQ(topts.retval, 0, "test_run");
+
+	result = (__u64 *)fentry_skel->bss;
+	for (i = 0; i < sizeof(*fentry_skel->bss) / sizeof(__u64); i++) {
+		if (!ASSERT_EQ(result[i], 1, "fentry_result"))
+			return -1;
+	}
+
+	fentry_test_lskel__detach(fentry_skel);
+
+	/* zero results for re-attach test */
+	memset(fentry_skel->bss, 0, sizeof(*fentry_skel->bss));
+	return 0;
+}
+
+void test_fentry_test(void)
+{
+	struct fentry_test_lskel *fentry_skel = NULL;
+	int err;
+
+	fentry_skel = fentry_test_lskel__open_and_load();
+	if (!ASSERT_OK_PTR(fentry_skel, "fentry_skel_load"))
+		goto cleanup;
+
+	err = fentry_test(fentry_skel);
+	if (!ASSERT_OK(err, "fentry_first_attach"))
+		goto cleanup;
+
+	err = fentry_test(fentry_skel);
+	ASSERT_OK(err, "fentry_second_attach");
+
+cleanup:
+	fentry_test_lskel__destroy(fentry_skel);
+}