Andrew S. Tanenbaum (OS) Edition 4 Exercise 2 Question 24 (Page No. 175)

Question

Does Peterson’s solution to the mutual-exclusion problem shown in Fig. $2-24$ work when process scheduling is preemptive? How about when it is nonpreemptive?

Comments

https://quizlet.com/53503150/operating-systems-flash-cards/

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@JEET

“Consider the case in which 'turn' is initially 0 but process 1 runs first. It will just loop forever and never release the CPU”

this is the example given in the link you shared but my doubt is how can ‘turn’ be 0 if process 1 runs first cause we are using the non preemptive scheduling,so the process which will set the turn variable will also be running and executing the CS.

I think the counter example for this should be if both interested variable for P0 and P1 process are initially true then it will lead to deadlock if its non preemptive

@srestha mam @shaik masthan sir please confirm

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Source : Tanenbaum 4e

Peterson solution does not require strict alteration.

But if it had strict alteration then there would have been problem.

Source: https://www.doc.ic.ac.uk/~etheresk/synchronisation-tutorial-sol.pdf