Suppose we have the Manna-Pnueli algorithm for mutual exclusion:
I was trying to find a sequence that violates mutual exclusion and I came up with this:
1. q1, q3; wantq=-1
2. p1
3. q4, q5; wantq=0
4. q1
5. p2; wantp=-1
6. p4
7. q3; wantq=-1
8. q4
9. p and q in critical section
Is my reasoning correct, supposing if is not atomic?
Also, were it atomic, how would I prove it to be correct? Should I just list all the possible combinations?
