Question

Considering the following algorithm, which of the following requirements are satisfied?

Considering the following algorithm, which of the following requirements are satisfied? int currentThread = 1; bool thread1 Access = true; bool thread2Access = true; thread1 { thread2 { While (true) { While (true) { while(thread2Access == true) { while(thread1Access == true) { If (currentThread == 2) { If (currentThread == 1) { thread1 Access = false; thread2Access = false; While (currentThread == 2); While (currentThread == 1); thread1 Access = true; thread2Access = true; /* start of critical section */ currentThread = 2 /* start of critical section */ currentThread = 1 ... /* end of critical section */ thread1Access = false; /* end of critical section */ thread2Access = false; a) Mutual Exclusion b) Bounded Waiting c) Progress d) None of the above

Answer 1

Initially cuscent Thread i. thread I Access = True thread 2 Access = Jouef. Now @t-o, thread 2 enless lie.executes). (threadl Access ==true) = True Ifleursent thread=21) True thread2 Access - F while (cument Thread --,);) 1 Threads a will Keep on loobing on this statement until Thread I makes culientThread=2. Thus Thread 2 cannot enter into critical section even though Thread 1 is not interested. Thus Progress is not guaranteed here. Check for mutual exclusion: Current Thread = V2 threadl access - T thread 2 access = @ t=0, Thread I executes (stats executing) Thread! makes thread I access =T and leaves . @t=1, Thread d entess - Gets looped into current Thread = al. Cannot enter into witical section. @ to 2, Threadı enter into citical section . Comes out of c.s. Make threadı Access - f. @t=3 curent Thread - 2. thread a enters cs. Thus at a given time , only one thread can enter cos... Thus mutual exclusion is guaranteed a

OLUN 3) Bounded Waiting: When threadl executes, it cannot into critical section untill thread a does not execute. Thus it guarantees bounded waiting None of the thread has to wait infinitely to enter C.s.
please upvote... I need it.. Thanks