#include <pthread.h>
#include <stdio.h>

long count1;
long count2;
volatile int stop;

void *thr_routine(void *arg)
{
	while (!stop) {
		(*(long *)arg)++;
		pthread_yield();
	}
	return (0);
}

void alarm_handler(int sig)
{
	stop = 1;
}

#define TIMEOUT 10

int main(int argc)
{
	pthread_t td1, td2;
	pthread_attr_t attr;

	pthread_setconcurrency(1);
	sleep(1);
	printf("testing scope process context switch speed...\n");
	signal(SIGALRM, alarm_handler);
	pthread_attr_init(&attr);
	pthread_attr_setscope(&attr, PTHREAD_SCOPE_PROCESS);
	pthread_attr_setcreatesuspend_np(&attr);
	pthread_create(&td1, &attr, thr_routine, &count1);
	pthread_create(&td2, &attr, thr_routine, &count2);
	alarm(TIMEOUT);
	pthread_resume_np(td1);
	pthread_resume_np(td2);
	pthread_join(td1, NULL);
	pthread_join(td2, NULL);
	printf("context switches:%ld/s\n", (count1+count2)/2/TIMEOUT);

	printf("testing scope system context switch speed...\n");
	count1 = 0;
	count2 = 0;
	stop = 0;
	pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM);
	pthread_create(&td1, &attr, thr_routine, &count1);
	pthread_create(&td2, &attr, thr_routine, &count2);
	pthread_attr_destroy(&attr);
	alarm(TIMEOUT);
	pthread_resume_np(td1);
	pthread_resume_np(td2);
	pthread_join(td1, NULL);
	pthread_join(td2, NULL);
	printf("context switches:%ld/s\n", (count1+count2)/2/TIMEOUT);
	return (0);
}