Ask HN: Multicore concurrency simulator

I have been teaching myself multicore programming and thus concurrent data structures in C/C++ and one problem I am facing is how best to (re)create contention situations between 2 or more cores, especially when trying to recreate read-write situations. Are there libraries/platforms/frameworks/sdks readily available that can ease or even solve this? For example, if I am trying to write a lock-free list data structure but I need to reliably create conditions under which a normal linked list data structure would be problematic to illustrate why a lock-free linked list is needed in the first place.