C code freezes/Pauses while execution

Hello,

I implemented the whole application on single core and it works fine. But when I just add one more core, I start facing the issues mentioned above. Code starts behaving weird. And I observed that, when my slave core(which i added later) is done with its operation/execution, the main core freezes. As per my app, slave core returns some values and master should continue its operation on returned values. I added print statements to debug, but the master stops printing once slave is done with its execution.

Please suggest. Having hard time with this.