minix/servers/pm/schedule.c
Tomas Hruby 86378ff645 PM remembers what it should schedule
- while PM implements fork also for RS it needs to remember what to
  schedule and what not. PM_SCHEDULED flag serves this purpose.

- PM only schedules processes that are descendaints of init, i.e. normal
  user processes

- after a process is forked PM schedules for the first time only
  processes that have PM_SCHEDULED set. The others are handled iether
  by kernel or some other scheduler
2010-04-13 10:45:08 +00:00

100 lines
2.6 KiB
C

#include "pm.h"
#include <minix/callnr.h>
#include <minix/com.h>
#include <minix/config.h>
#include <minix/sysinfo.h>
#include <minix/type.h>
#include <machine/archtypes.h>
#include <lib.h>
#include "mproc.h"
#include "kernel/proc.h" /* for MIN_USER_Q */
PRIVATE timer_t sched_timer;
/*
* makes a kernel call that schedules the process using the actuall scheduling
* parameters set for this process
*/
PUBLIC int schedule_process(struct mproc * rmp)
{
int err;
if ((err = sys_schedule(rmp->mp_endpoint, rmp->mp_priority,
rmp->mp_time_slice)) != OK) {
printf("PM: An error occurred when trying to schedule %s: %d\n",
rmp->mp_name, err);
}
return err;
}
/*===========================================================================*
* do_noquantum *
*===========================================================================*/
PUBLIC void do_noquantum(void)
{
int rv, proc_nr_n;
register struct mproc *rmp;
if (pm_isokendpt(m_in.m_source, &proc_nr_n) != OK) {
printf("PM: WARNING: got an invalid endpoint in OOQ msg %u.\n",
m_in.m_source);
return;
}
rmp = &mproc[proc_nr_n];
if (rmp->mp_priority < MIN_USER_Q) {
rmp->mp_priority += 1; /* lower priority */
}
schedule_process(rmp);
}
/*===========================================================================*
* overtake_scheduling *
*===========================================================================*/
PUBLIC void overtake_scheduling(void)
{
struct mproc *trmp;
int proc_nr;
tmr_inittimer(&sched_timer);
for (proc_nr=0, trmp=mproc; proc_nr < NR_PROCS; proc_nr++, trmp++) {
/* Don't overtake system processes. When the system starts,
* this will typically only overtake init, from which other
* user space processes will inherit. */
if (trmp->mp_flags & IN_USE && !(trmp->mp_flags & PRIV_PROC)) {
if (sys_schedctl(trmp->mp_endpoint))
printf("PM: Error while overtaking scheduling for %s\n",
trmp->mp_name);
trmp->mp_flags |= PM_SCHEDULED;
}
}
pm_set_timer(&sched_timer, 100, balance_queues, 0);
}
/*===========================================================================*
* balance_queues *
*===========================================================================*/
PUBLIC void balance_queues(tp)
struct timer *tp;
{
struct mproc *rmp;
int proc_nr;
int rv;
for (proc_nr=0, rmp=mproc; proc_nr < NR_PROCS; proc_nr++, rmp++) {
if (rmp->mp_flags & IN_USE) {
if (rmp->mp_priority > rmp->mp_max_priority) {
rmp->mp_priority -= 1; /* increase priority */
schedule_process(rmp);
}
}
}
pm_set_timer(&sched_timer, 100, balance_queues, 0);
}