1
GATE CSE 2001
MCQ (Single Correct Answer)
+1
-0.3
A processor needs software interrupt to
A
Test the interrupt system of the processor
B
Implement co-routines
C
Obtain system services which need execution of privileged instructions
D
Return from subroutine
2
GATE CSE 2001
MCQ (Single Correct Answer)
+1
-0.3
Suppose a processor does not have any stack pointer register. Which of the following statements is true?
A
It cannot have subroutine call instruction
B
It can have subroutine call instruction, but no nested subroutine calls
C
Nested subroutine calls are possible, but interrupts are not
D
All sequences of subroutine call and also interrupts are possible
3
GATE CSE 2001
MCQ (Single Correct Answer)
+2
-0.6
Consider Peterson’s algorithm for mutual exclusion between two concurrent processes i and j. The program executed by process is shown below.
 Repeat 
     flag[i]=true; 
     turn=j; 
     while (P) do no-op; 
     Enter critical section, perform actions, then 
     exit critical section 
     Flag[i]=false; 
     Perform other non-critical section actions. 
 Until false;
For the program to guarantee mutual exclusion, the predicate P in the while loop should be
A
flag[j]=true and turn=i
B
flag[j]=true and turn=j
C
flag[i]=true and turn=j
D
flag[i]=true and turn=i
4
GATE CSE 2001
MCQ (Single Correct Answer)
+1
-0.3
Where does the swap space reside?
A
RAM
B
Disk
C
ROM
D
On-chip cache