#include <stdio.h>

int main() 
{ 
	unsigned int regr;
	unsigned int i;
	unsigned int a, b;

	asm volatile("mrc p15, 0, %0, c9, c14, 0" : "=r" (regr));
	printf("regr: %x\n", regr);

	regr = 0;
	while ( regr < 10)
	{
		asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (a));
		i = getpid();
		asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (b));

		printf("PID: %u, Time for getpid: %u\n", i, b - a);
		regr++;
	}
	return 1; 
}