bpf_cgroup_read_xattr
BTF_ID_FLAGS(func, bpf_cgroup_read_xattr, KF_RCU)
extern int bpf_cgroup_read_xattr(struct cgroup *cgroup, const char *name__str,
bpf_cgroup_read_xattr(cgroup, "user.bpf_test",
ret = bpf_cgroup_read_xattr(tmp->cgroup, "user.bpf_test",