Softlockup and Hardlockup sample test module

Hi All, Could you please provide some sample test module for causing a Softlockup and Hardlockup in latest kernel for SMP for testing purposes. I assume there are some Kconfigs to be enabled as well for this. I had tried with the module where I put a busy loop inside spinlock but was not able to cause any lockups. Maybe this is because of SMP which schedule the job to other CPU. "How do I make a task to run on single CPU only?" I only get RCU stalls sometimes instead of softlockup when I use busy loop inside a spinlock. Is there any explanation for difference between these stalls and softlockup. Thanks, IVID