Consider the following program P1 P2 shared int x shared int x x
Subject:Computer Science
Consider the following program:
P1: { P2: {
shared int x; shared int x;
x = 10; x = 10;
while (1) { while ( 1 ) {
x = x - 1; x = x - 1;
x = x + 1; x = x + 1;
if (x != 10) if (x!=10)
printf(“x is %d”,x) printf(“x is %d”,x)
} }
} }
Note the scheduler in a uniprocessor system would implement pseudo-parallel execution of these two concurrent processes by interleaving their instructions, without restriction on the order of the interleaving.
Show a sequence (i.e., trace the sequence of interleavings of statements) such that the statement “x is 10” is printed.
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Answer The program you've provided is a classic example of a race condition, where two or more threads are accessing and manipulating the same shared data concurrently. The final
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