servers/pm/schedule.c

   1 #include "pm.h"
   2 #include <minix/callnr.h>
   3 #include <minix/com.h>
   4 #include <minix/config.h>
   5 #include <minix/sysinfo.h>
   6 #include <minix/type.h>
   7 #include <machine/archtypes.h>
   8 #include <lib.h>
   9 #include "mproc.h"
  10 #include "kernel/proc.h" /* for MIN_USER_Q */
  11
  12 PRIVATE timer_t sched_timer;
  13
  14 /*
  15  * makes a kernel call that schedules the process using the actuall scheduling
  16  * parameters set for this process
  17  */
  18 PUBLIC int schedule_process(struct mproc * rmp)
  19 {
  20         int err;
  21
  22         if ((err = sys_schedule(rmp->mp_endpoint, rmp->mp_priority,
  23                 rmp->mp_time_slice)) != OK) {
  24                 printf("PM: An error occurred when trying to schedule %s: %d\n",
  25                 rmp->mp_name, err);
  26         }
  27
  28         return err;
  29 }
  30
  31 /*===========================================================================*
  32  *                              do_noquantum                                 *
  33  *===========================================================================*/
  34
  35 PUBLIC void do_noquantum(void)
  36 {
  37         int rv, proc_nr_n;
  38         register struct mproc *rmp;
  39
  40         if (pm_isokendpt(m_in.m_source, &proc_nr_n) != OK) {
  41                 printf("PM: WARNING: got an invalid endpoint in OOQ msg %u.\n",
  42                 m_in.m_source);
  43                 return;
  44         }
  45
  46         rmp = &mproc[proc_nr_n];
  47         if (rmp->mp_priority < MIN_USER_Q) {
  48                 rmp->mp_priority += 1; /* lower priority */
  49         }
  50
  51         schedule_process(rmp);
  52 }
  53
  54 /*===========================================================================*
  55  *                              takeover_scheduling                          *
  56  *===========================================================================*/
  57 PUBLIC void takeover_scheduling(void)
  58 {
  59         struct mproc *trmp;
  60         int proc_nr;
  61
  62         tmr_inittimer(&sched_timer);
  63
  64         for (proc_nr=0, trmp=mproc; proc_nr < NR_PROCS; proc_nr++, trmp++) {
  65                 /* Don't takeover system processes. When the system starts,
  66                  * this will typically only takeover init, from which other
  67                  * user space processes will inherit. */
  68                 if (trmp->mp_flags & IN_USE && !(trmp->mp_flags & PRIV_PROC)) {
  69                         if (sys_schedctl(trmp->mp_endpoint))
  70                                 printf("PM: Error while taking over scheduling for %s\n",
  71                                         trmp->mp_name);
  72                         trmp->mp_flags |= PM_SCHEDULED;
  73                 }
  74         }
  75
  76         pm_set_timer(&sched_timer, 100, balance_queues, 0);
  77 }
  78
  79 /*===========================================================================*
  80  *                              balance_queues                               *
  81  *===========================================================================*/
  82
  83 PUBLIC void balance_queues(tp)
  84 struct timer *tp;
  85 {
  86         struct mproc *rmp;
  87         int proc_nr;
  88         int rv;
  89
  90         for (proc_nr=0, rmp=mproc; proc_nr < NR_PROCS; proc_nr++, rmp++) {
  91                 if (rmp->mp_flags & IN_USE) {
  92                         if (rmp->mp_priority > rmp->mp_max_priority) {
  93                                 rmp->mp_priority -= 1; /* increase priority */
  94                                 schedule_process(rmp);
  95                         }
  96                 }
  97         }
  98
  99         pm_set_timer(&sched_timer, 100, balance_queues, 0);
 100 }