INFOF410 - Real Time Linux Task 3

gistfile1.c

// ---------------------------------------------------------------------
// exemple-threads-temps-reel.c
// Adapté d'un ficher d'exemple du livre "Solutions Temps-Reel sous Linux"
// (C) 2012 - Christophe BLAESS
// http://christophe.blaess.fr
// ---------------------------------------------------------------------

#include <pthread.h>
#include <sched.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>

#define NB_THREADS 4

void * fonction_thread(void * arg)
{
	int numero = (int) arg;
	int i, j;

	sleep(numero*2);

	fprintf(stderr, "Debut thread %d a %ld\n", numero, time(NULL));
	for (i = 0; i < 100000; i ++) {
		if (i%1000==0) fprintf(stderr, "%d",numero) ;
		for (j = 0; j < 10000; j ++)
			;
	}
			
	fprintf(stderr, "Fin thread %d a %ld\n", numero, time(NULL));
	return NULL;
}

int main(void)
{	
	
	int priorities[4] = {60, 55, 50, 45};
	pthread_t thr[NB_THREADS];
	pthread_attr_t attributes;//reusable
	struct sched_param parameters;//reusable

	pthread_attr_init(&attributes);//Default init
	pthread_attr_setschedpolicy(&attributes, SCHED_FIFO);//Scheduling policy
	pthread_attr_setinheritsched(&attributes, PTHREAD_EXPLICIT_SCHED);//Activate the value set in attributes. Otherwise, value ignored and parent's inheritage.

	int i;
	for(i=0;i<NB_THREADS;++i) {
		printf("Loop #%d", i);

		parameters.sched_priority = priorities[i];//Priority
		pthread_attr_setschedparam(&attributes, &parameters);//Set priority
		pthread_create(&thr[i], &attributes, fonction_thread, (void *)i);
	}


	/* Créer NB_THREADS threads temps réel qui exécutent chacun la fonction fonction_thread 
	   ci-dessus avec un numéro différent (0...NB_THREADS-1)*/

	for (i = 0; i < NB_THREADS; i ++)
		pthread_join(thr[i], NULL);

	return EXIT_SUCCESS;
}