/* returns one if linking was redirected */
static int pfair_link(quanta_t time, int cpu,
struct task_struct* t)
{
int target = target_cpu(time, t, cpu);
struct task_struct* prev = pstate[cpu]->linked;
struct task_struct* other;
if (target != cpu) {
other = pstate[target]->linked;
pstate[target]->linked = t;
tsk_rt(t)->linked_on = target;
if (!other)
/* linked ok, but reschedule this CPU */
return 1;
if (target < cpu) {
/* link other to cpu instead */
tsk_rt(other)->linked_on = cpu;
pstate[cpu]->linked = other;
if (prev) {
/* prev got pushed back into the ready queue */
tsk_rt(prev)->linked_on = NO_CPU;
__add_ready(&pfair, prev);
}
/* we are done with this cpu */
return 0;
} else {
/* re-add other, it's original CPU was not considered yet */
tsk_rt(other)->linked_on = NO_CPU;
__add_ready(&pfair, other);
/* reschedule this CPU */
return 1;
}
} else {
pstate[cpu]->linked = t;
tsk_rt(t)->linked_on = cpu;
if (prev) {
/* prev got pushed back into the ready queue */
tsk_rt(prev)->linked_on = NO_CPU;
__add_ready(&pfair, prev);
}
/* we are done with this CPU */
return 0;
}
}
static void requeue(struct task_struct* t, rt_domain_t *edf)
{
if (t->state != TASK_RUNNING)
TRACE_TASK(t, "requeue: !TASK_RUNNING\n");
tsk_rt(t)->completed = 0;
if (is_early_releasing(t) || is_released(t, litmus_clock()))
__add_ready(edf, t);
else
add_release(edf, t); /* it has got to wait */
}
/* Add the task `tsk` to the appropriate queue. Assumes the caller holds the ready lock.
*/
static void demo_requeue(struct task_struct *tsk, struct demo_cpu_state *cpu_state)
{
if (is_released(tsk, litmus_clock())) {
/* Uses __add_ready() instead of add_ready() because we already
* hold the ready lock. */
__add_ready(&cpu_state->local_queues, tsk);
} else {
/* Uses add_release() because we DON'T have the release lock. */
add_release(&cpu_state->local_queues, tsk);
}
}
