1 files changed, 91 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_global_func_args.c b/tools/testing/selftests/bpf/progs/test_global_func_args.c
new file mode 100644
index 000000000000..e712bf77daae
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_global_func_args.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+
+#include <bpf/bpf_helpers.h>
+
+struct S {
+	int v;
+};
+
+struct S global_variable = {};
+
+struct {
+	__uint(type, BPF_MAP_TYPE_ARRAY);
+	__uint(max_entries, 7);
+	__type(key, __u32);
+	__type(value, int);
+} values SEC(".maps");
+
+static void save_value(__u32 index, int value)
+{
+	bpf_map_update_elem(&values, &index, &value, 0);
+}
+
+__noinline int foo(__u32 index, struct S *s)
+{
+	if (s) {
+		save_value(index, s->v);
+		return ++s->v;
+	}
+
+	save_value(index, 0);
+
+	return 1;
+}
+
+__noinline int bar(__u32 index, volatile struct S *s)
+{
+	if (s) {
+		save_value(index, s->v);
+		return ++s->v;
+	}
+
+	save_value(index, 0);
+
+	return 1;
+}
+
+__noinline int baz(struct S **s)
+{
+	if (s)
+		*s = 0;
+
+	return 0;
+}
+
+SEC("cgroup_skb/ingress")
+int test_cls(struct __sk_buff *skb)
+{
+	__u32 index = 0;
+
+	{
+		const int v = foo(index++, 0);
+
+		save_value(index++, v);
+	}
+
+	{
+		struct S s = { .v = 100 };
+
+		foo(index++, &s);
+		save_value(index++, s.v);
+	}
+
+	{
+		global_variable.v = 42;
+		bar(index++, &global_variable);
+		save_value(index++, global_variable.v);
+	}
+
+	{
+		struct S v, *p = &v;
+
+		baz(&p);
+		save_value(index++, !p);
+	}
+
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";