Counting Barrier - Georgia Tech - Advanced Operating Systems

[sanketitnal]

I think that potential deadlock is the main problem with these approaches. Let's say that all threads waiting for count to be zero have been preempted for some reason. If the last thread decrements the count and sets count = N, the preempted threads when woken up will still be waiting for the count to become zero. This is a deadlock situation.

[abhayshukla]

why not remove the while(count > 0) spin ?? It will still work i suppose, and we will have only 1 spin.