Profiling Threads in Pro

I am currently attempting to use the Unity Profiler to profile some CPU-intensive code, but, it doesn’t seem to be showing up in the Profiler. When I attempt to add a Profiler.BeginSample()/EndSample() around the code, I get an error that it can only be done from the main thread, as I have several threads doing the heavy work.

Furthermore, the Profiler seems to be only showing info about code that is run directly through the Unity engine/main thread.

Am I missing something? I was hoping the Profiler in Pro (I am using the trial for now) was more inclusive. What am I missing?

So basically the Unity Profiler only profiles Unity-specific code? I was hoping it’d give a more specific breakdown, like, "you made 4000 calls to ‘cast int’ or ‘func_x()’.