call_rcu(test_cb1, old);
call_rcu(test_cb1, (void *)-2L);
call_rcu(test_cb1, (void *)-2L);
call_rcu(test_cb1, old);
call_rcu(test_cb2, (void *)-2L);
call_rcu(test_cb1, old);
call_rcu(test_cb1, (void *)-2L);
call_rcu(test_cb1, (void *)-2L);
call_rcu(test_cb1, old);
call_rcu(test_cb2, (void *)-2L);