lib/libsys/sched_start.c

   1 #include "syslib.h"
   2 #include <assert.h>
   3 #include <machine/archtypes.h>
   4 #include <timers.h>
   5
   6 #include "kernel/config.h"
   7 #include "kernel/const.h"
   8 #include "kernel/type.h"
   9 #include "kernel/proc.h"
  10
  11 /*===========================================================================*
  12  *                              sched_inherit                                *
  13  *===========================================================================*/
  14 int sched_inherit(endpoint_t scheduler_e,
  15         endpoint_t schedulee_e, endpoint_t parent_e, unsigned maxprio,
  16         endpoint_t *newscheduler_e)
  17 {
  18         int rv;
  19         message m;
  20
  21         assert(_ENDPOINT_P(scheduler_e) >= 0);
  22         assert(_ENDPOINT_P(schedulee_e) >= 0);
  23         assert(_ENDPOINT_P(parent_e) >= 0);
  24         assert(maxprio < NR_SCHED_QUEUES);
  25         assert(newscheduler_e);
  26
  27         m.SCHEDULING_ENDPOINT   = schedulee_e;
  28         m.SCHEDULING_PARENT     = parent_e;
  29         m.SCHEDULING_MAXPRIO    = (int) maxprio;
  30
  31         /* Send the request to the scheduler */
  32         if ((rv = _taskcall(scheduler_e, SCHEDULING_INHERIT, &m))) {
  33                 return rv;
  34         }
  35
  36         /* Store the process' scheduler. Note that this might not be the
  37          * scheduler we sent the SCHEDULING_INHERIT message to. That scheduler
  38          * might have forwarded the scheduling message on to another scheduler
  39          * before returning the message.
  40          */
  41         *newscheduler_e = m.SCHEDULING_SCHEDULER;
  42         return (OK);
  43 }
  44
  45 /*===========================================================================*
  46  *                              sched_start                                  *
  47  *===========================================================================*/
  48 int sched_start(endpoint_t scheduler_e,
  49                         endpoint_t schedulee_e,
  50                         endpoint_t parent_e,
  51                         int maxprio,
  52                         int quantum,
  53                         int cpu,
  54                         endpoint_t *newscheduler_e)
  55 {
  56         int rv;
  57         message m;
  58
  59         /* No scheduler given? We are done. */
  60         if(scheduler_e == NONE) {
  61                 return OK;
  62         }
  63
  64         assert(_ENDPOINT_P(schedulee_e) >= 0);
  65         assert(_ENDPOINT_P(parent_e) >= 0);
  66         assert(maxprio >= 0);
  67         assert(maxprio < NR_SCHED_QUEUES);
  68         assert(quantum > 0);
  69         assert(newscheduler_e);
  70
  71         /* The KERNEL must schedule this process. */
  72         if(scheduler_e == KERNEL) {
  73                 if ((rv = sys_schedctl(SCHEDCTL_FLAG_KERNEL,
  74                         schedulee_e, maxprio, quantum, cpu)) != OK) {
  75                         return rv;
  76                 }
  77                 *newscheduler_e = scheduler_e;
  78                 return OK;
  79         }
  80
  81         /* A user-space scheduler must schedule this process. */
  82         m.SCHEDULING_ENDPOINT   = schedulee_e;
  83         m.SCHEDULING_PARENT     = parent_e;
  84         m.SCHEDULING_MAXPRIO    = (int) maxprio;
  85         m.SCHEDULING_QUANTUM    = (int) quantum;
  86
  87         /* Send the request to the scheduler */
  88         if ((rv = _taskcall(scheduler_e, SCHEDULING_START, &m))) {
  89                 return rv;
  90         }
  91
  92         /* Store the process' scheduler. Note that this might not be the
  93          * scheduler we sent the SCHEDULING_START message to. That scheduler
  94          * might have forwarded the scheduling message on to another scheduler
  95          * before returning the message.
  96          */
  97         *newscheduler_e = m.SCHEDULING_SCHEDULER;
  98         return (OK);
  99 }