1 files changed, 59 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_stress.c b/tools/testing/selftests/bpf/prog_tests/fexit_stress.c
new file mode 100644
index 000000000..596536def
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/fexit_stress.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Facebook */
+#include <test_progs.h>
+
+void serial_test_fexit_stress(void)
+{
+	int bpf_max_tramp_links, err, i;
+	int *fd, *fexit_fd, *link_fd;
+
+	bpf_max_tramp_links = get_bpf_max_tramp_links();
+	if (!ASSERT_GE(bpf_max_tramp_links, 1, "bpf_max_tramp_links"))
+		return;
+	fd = calloc(bpf_max_tramp_links * 2, sizeof(*fd));
+	if (!ASSERT_OK_PTR(fd, "fd"))
+		return;
+	fexit_fd = fd;
+	link_fd = fd + bpf_max_tramp_links;
+
+	const struct bpf_insn trace_program[] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_EXIT_INSN(),
+	};
+
+	LIBBPF_OPTS(bpf_prog_load_opts, trace_opts,
+		.expected_attach_type = BPF_TRACE_FEXIT,
+	);
+
+	LIBBPF_OPTS(bpf_test_run_opts, topts);
+
+	err = libbpf_find_vmlinux_btf_id("bpf_fentry_test1",
+					 trace_opts.expected_attach_type);
+	if (!ASSERT_GT(err, 0, "find_vmlinux_btf_id"))
+		goto out;
+	trace_opts.attach_btf_id = err;
+
+	for (i = 0; i < bpf_max_tramp_links; i++) {
+		fexit_fd[i] = bpf_prog_load(BPF_PROG_TYPE_TRACING, NULL, "GPL",
+					    trace_program,
+					    sizeof(trace_program) / sizeof(struct bpf_insn),
+					    &trace_opts);
+		if (!ASSERT_GE(fexit_fd[i], 0, "fexit load"))
+			goto out;
+		link_fd[i] = bpf_link_create(fexit_fd[i], 0, BPF_TRACE_FEXIT, NULL);
+		if (!ASSERT_GE(link_fd[i], 0, "fexit attach"))
+			goto out;
+	}
+
+	err = bpf_prog_test_run_opts(fexit_fd[0], &topts);
+	ASSERT_OK(err, "bpf_prog_test_run_opts");
+
+out:
+	for (i = 0; i < bpf_max_tramp_links; i++) {
+		if (link_fd[i])
+			close(link_fd[i]);
+		if (fexit_fd[i])
+			close(fexit_fd[i]);
+	}
+	free(fd);
+}