Exit loadtest from setup script

I have created a setup script for my loadtest which is reading some config from a config file.
In case of missing values, I want to exit my loadtest.

I have tried the following :

1. throw new Exception("blabla")
This exits the setup script, but the loadtest continues.

2. loadTestRunner.fail("blabla")
The loadtest is still executed.

Does anybode have an idea how I can just cancel the load test ?