/*
 * Simple loop testing the CPU-affinity syscall.
 */
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <linux/unistd.h>

#define __NR_sched_set_affinity 226
_syscall3 (int, sched_set_affinity, pid_t, pid, unsigned int, mask_len, unsigned long *, mask)

#define __NR_sched_get_affinity 227
_syscall3 (int, sched_get_affinity, pid_t, pid, unsigned int *, mask_len, unsigned long *, mask)

int main (int argc, char **argv)
{
	int pid, ret;
	unsigned int mask_len;
	unsigned long mask, new_mask;

	if (argc != 3) {
		printf("usage: chaff <pid> <hex_mask>\n");
		exit(-1);
	}
	pid = atol(argv[1]);
	sscanf(argv[2], "%lx", &new_mask);

printf("pid: %d. new_mask: (%s) %08lx.\n", pid, argv[2], new_mask);

	ret = sched_get_affinity(pid, &mask_len, &mask);
	if (ret) {
		printf("could not get pid %d's affinity.\n", pid);
		return -1;
	}
	printf("pid %d's old affinity: %08lx.", pid, mask);

	ret = sched_set_affinity(pid, sizeof(new_mask), &new_mask);
	if (ret) {
		printf("could not set pid %d's affinity.\n", pid);
		return -1;
	}
	ret = sched_get_affinity(pid, &mask_len, &mask);
	if (ret) {
		printf("sched_get_affinity returned %d, exiting.\n", ret);
		return -1;
	}
	printf("pid %d's new affinity: %08lx.", pid, mask);
	return 0;
}