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New scheduling code in kernel. Work in progress.

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Round-robin within one priority queue works fine.
Ageing algorithm to be done.
This commit is contained in:
Jorrit Herder
2005-08-19 16:43:28 +00:00
parent d45066257c
commit a01645b788
18 changed files with 164 additions and 136 deletions
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27
kernel/clock.c
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@@ -112,6 +112,17 @@ message *m_ptr; /* pointer to request message */
* is called on those clock ticks when a lot of work needs to be done.
*/
/* A process used up a full quantum. The interrupt handler stored this
* process in 'prev_ptr'. First make sure that the process is not on the
* scheduling queues. Then announce the process ready again. Since it has
* no more time left, it will get a new quantum and inserted at the right
* place in the queues. As a side-effect a new process will be scheduled.
*/
if (prev_ptr->p_sched_ticks <= 0 && priv(prev_ptr)->s_flags & PREEMPTIBLE) {
lock_dequeue(prev_ptr); /* take it off the queues */
lock_enqueue(prev_ptr); /* and reinsert it again */
}
/* Check if a clock timer expired and run its watchdog function. */
if (next_timeout <= realtime) {
tmrs_exptimers(&clock_timers, realtime, NULL);
@@ -119,13 +130,6 @@ message *m_ptr; /* pointer to request message */
TMR_NEVER : clock_timers->tmr_exp_time;
}
/* A process used up a full quantum. The interrupt handler stored this
* process in 'prev_ptr'. Reset the quantum and schedule another process.
*/
if (prev_ptr->p_sched_ticks <= 0) {
lock_sched(prev_ptr);
}
/* Inhibit sending a reply. */
return(EDONTREPLY);
}
@@ -177,8 +181,13 @@ irq_hook_t *hook;
* Thus the unbillable process' user time is the billable user's system time.
*/
proc_ptr->p_user_time += ticks;
if (proc_ptr != bill_ptr) bill_ptr->p_sys_time += ticks;
if (priv(proc_ptr)->s_flags & PREEMPTIBLE) proc_ptr->p_sched_ticks -= ticks;
if (priv(proc_ptr)->s_flags & PREEMPTIBLE) {
proc_ptr->p_sched_ticks -= ticks;
}
if (! (priv(proc_ptr)->s_flags & BILLABLE)) {
bill_ptr->p_sys_time += ticks;
bill_ptr->p_sched_ticks -= ticks;
}
/* Check if do_clocktick() must be called. Done for alarms and scheduling.
* Some processes, such as the kernel tasks, cannot be preempted.