void update_process_cycles(void)
{
	struct task_struct *p = current;
	int cpu = smp_processor_id();
	cycles_t t = get_cycles();

	p->cycles[cpu] += t - last_cycles[cpu];
	if ( p->pid )
	    kstat.used_cycles[cpu] += t - last_cycles[cpu];
	last_cycles[cpu] = t;
}