/*!
* Deactivate thread because:
* 1. higher priority thread becomes active
* 2. this thread time slice is expired
* 3. this thread blocks on some queue
*/
static int rr_thread_deactivate ( kthread_t *kthread )
{
/* Get current time and recalculate remainder */
time_t t;
kthread_sched_data_t *tsched = kthread_get_sched_param ( kthread );
ksched_t *gsched = ksched_get ( tsched->sched_policy );
if (tsched->params.rr.remainder.sec + tsched->params.rr.remainder.nsec)
{
/*
* "slice interrupted"
* recalculate remainder
*/
k_get_time ( &t );
time_sub ( &tsched->params.rr.slice_end, &t );
tsched->params.rr.remainder = tsched->params.rr.slice_end;
if ( kthread_is_ready ( kthread ) )
{
/* is remainder too small or not? */
if ( time_cmp ( &tsched->params.rr.remainder,
&gsched->params.rr.threshold ) <= 0 )
{
kthread_move_to_ready ( kthread, LAST );
}
else {
kthread_move_to_ready ( kthread, FIRST );
}
}
}
/* else = remainder is zero, thread is already enqueued in ready queue*/
return 0;
}
int k_delayed_send(int destination_proc_id, void *message_envelope, int delay) {
msg_metadata *metadata = reserve_message_metadata(message_envelope);
if (metadata == NULL) {
return RTX_ERR;
}
if (message_envelope == NULL) {
uart1_put_string("k_send_message is NULL. Bad!\n");
return RTX_ERR;
}
__disable_irq();
metadata->sender_pid = gp_current_process->pid;
metadata->destination_pid = destination_proc_id;
metadata->send_time = k_get_time() + delay;
if (g_delayed_messages_count == (BLOCK_SIZE / sizeof(void *))) {
// Overflow is... unlikely.
ASSERT(0)
}
g_delayed_messages[g_delayed_messages_count++] = message_envelope;
__enable_irq();
return RTX_OK;
}
/*! Start time slice for thread (or countinue interrupted) */
static int rr_thread_activate ( kthread_t *kthread )
{
kthread_sched_data_t *tsched = kthread_get_sched_param ( kthread );
ksched_t *gsched = ksched_get ( tsched->sched_policy );
/* check remainder if needs to be replenished */
if ( time_cmp ( &tsched->params.rr.remainder,
&gsched->params.rr.threshold ) <= 0 )
{
time_add ( &tsched->params.rr.remainder,
&gsched->params.rr.time_slice );
}
/* Get current time and store it */
k_get_time ( &tsched->params.rr.slice_start );
/* When to wake up? */
tsched->params.rr.slice_end = tsched->params.rr.slice_start;
time_add ( &tsched->params.rr.slice_end, &tsched->params.rr.remainder );
/* Set alarm for remainder time */
gsched->params.rr.alarm.exp_time = tsched->params.rr.slice_end;
gsched->params.rr.alarm.param = kthread;
k_alarm_set ( gsched->params.rr.rr_alarm, &gsched->params.rr.alarm );
return 0;
}
/*!
* Get current time
* \param time Pointer where to store time
* \return status
*/
int sys__get_time ( time_t *time )
{
ASSERT_ERRNO_AND_EXIT ( time, E_INVALID_HANDLE );
disable_interrupts ();
k_get_time ( time );
enable_interrupts ();
EXIT ( SUCCESS );
}
/*!
* Get current time
* \param time Pointer where to store time
* \returns status
*/
int sys__get_time ( void *p )
{
time_t *time;
time = *( (void **) p );
ASSERT_ERRNO_AND_EXIT ( time, E_INVALID_HANDLE );
k_get_time ( time );
EXIT ( SUCCESS );
}
//int sys__get_time ( time_t *time )
int sys__get_time ( void *p )
{
time_t *time;
time = *( (void **) p );
ASSERT_ERRNO_AND_EXIT ( time, E_INVALID_HANDLE );
time = U2K_GET_ADR ( time, k_get_active_process() );
k_get_time ( time );
EXIT ( SUCCESS );
}
/*!
* Check if task hasn't overrun its deadline at its start
* Handle deadline overrun, based on flags
*/
static int edf_check_deadline ( kthread_t *kthread )
{
/*
* Check if "now" is greater than "active_deadline"
*/
time_t now;
kthread_sched_data_t *tsched = kthread_get_sched_param ( kthread );
k_get_time ( &now );
if ( time_cmp ( &now, &tsched->params.edf.active_deadline ) > 0 )
{
LOG( DEBUG, "%x [DEADLINE OVERRUN]", kthread );
return -1;
}
return 0;
}
static int edf_set_thread_sched_parameters (kthread_t *kthread, sched_t *params)
{
time_t now;
alarm_t alarm;
kthread_sched_data_t *tsched = kthread_get_sched_param ( kthread );
ksched_t *gsched = ksched_get ( SCHED_EDF );
if ( gsched->params.edf.active == kthread )
gsched->params.edf.active = NULL;
k_get_time ( &now );
if ( params->edf.flags & EDF_SET )
{
/*LOG( DEBUG, "%x [SET]", kthread ); */
tsched->params.edf.period = params->edf.period;
tsched->params.edf.relative_deadline = params->edf.deadline;
tsched->params.edf.flags = params->edf.flags;
/* set periodic alarm */
tsched->params.edf.next_run = now;
time_add ( &tsched->params.edf.next_run, ¶ms->edf.period );
edf_arm_deadline ( kthread );
edf_arm_period ( kthread );
/*
* adjust "next_run" and "deadline" for "0" period
* - first "edf_wait" will set correct values for first period
*/
tsched->params.edf.next_run = now;
time_sub ( &tsched->params.edf.next_run, ¶ms->edf.period );
tsched->params.edf.active_deadline = now;
time_add ( &tsched->params.edf.active_deadline,
¶ms->edf.deadline );
}
else if ( params->edf.flags & EDF_WAIT )
{
if ( edf_check_deadline ( kthread ) )
return -1;
/* set times for next period */
if ( time_cmp ( &now, &tsched->params.edf.next_run ) > 0 )
{
time_add ( &tsched->params.edf.next_run,
&tsched->params.edf.period );
tsched->params.edf.active_deadline = tsched->params.edf.next_run;
time_add ( &tsched->params.edf.active_deadline,
&tsched->params.edf.relative_deadline );
if ( kthread == gsched->params.edf.active )
gsched->params.edf.active = NULL;
/* set (separate) alarm for deadline */
alarm.action = edf_deadline_timer;
alarm.param = kthread;
alarm.flags = 0;
alarm.period.sec = alarm.period.nsec = 0;
alarm.exp_time = tsched->params.edf.active_deadline;
k_alarm_set ( tsched->params.edf.edf_deadline_alarm, &alarm );
}
/* is task ready for execution, or must wait until next period */
if ( time_cmp ( &tsched->params.edf.next_run, &now ) > 0 )
{
/* wait till "next_run" */
LOG( DEBUG, "%x [EDF WAIT]", kthread );
kthread_enqueue ( kthread, &gsched->params.edf.wait );
kthreads_schedule (); /* will call edf_schedule() */
}
else {
/* "next_run" has already come,
* activate task => move it to "EDF ready tasks"
*/
LOG( DEBUG, "%x [EDF READY]", kthread );
LOG( DEBUG, "%x [1st READY]", kthreadq_get ( &gsched->params.edf.ready ) );
kthread_enqueue ( kthread, &gsched->params.edf.ready );
kthreads_schedule (); /* will call edf_schedule() */
}
}
else if ( params->edf.flags & EDF_EXIT )
{
if ( kthread == gsched->params.edf.active )
gsched->params.edf.active = NULL;
//LOG( DEBUG, "%x [EXIT]", kthread );
if ( edf_check_deadline ( kthread ) )
{
LOG( DEBUG, "%x [EXIT-error]", kthread );
return -1;
}
LOG( DEBUG, "%x [EXIT-normal]", kthread );
if ( tsched->params.edf.edf_period_alarm )
k_alarm_remove ( tsched->params.edf.edf_period_alarm );
if ( tsched->params.edf.edf_deadline_alarm )
k_alarm_remove ( tsched->params.edf.edf_deadline_alarm );
tsched->sched_policy = SCHED_FIFO;
LOG( DEBUG, "%x [EXIT]", kthread );
if ( k_edf_schedule () )
{
LOG( DEBUG, "%x [EXIT]", kthread );
kthreads_schedule (); /* will NOT call edf_schedule() */
}
LOG( DEBUG, "%x [EXIT]", kthread );
}
return 0;
}
