I'm working on Linux kernel 2.4 (homework) and I inserted the following code into the scheduler_tick function:

if (unlikely(rt_task(p)) || (p->policy==SCHED_PROD && 
            p->time_ran>=p->process_expected_time)) {
    /*
     * RR tasks need a special form of timeslice management.
     * FIFO tasks have no timeslices.
     */
    if ((p->policy == SCHED_RR || /*change*/p->policy==SCHED_PROD) && !--p->time_slice) {
        /*changes*/
        if (p->policy == SCHED_PROD){
            for (i=0; i<5000; i++){
                printk("I'm leeching off SCHED_RR code! %d\n", i);
            }
        }
        /*end changes*/

The addition was added for debugging purposes. For some reason this causes very weird behavior: when a SCHED_PROD process triggers this code (and consequently the loop that follows) the loop counts to about 4600 normally, but then goes back to 4600 each time it counts to 4800, and gets stuck in an infinite loop.

What's going on??

EDIT: The i variable is my own.