minix/servers/pm/schedule.c
Tomas Hruby 06b6e5624a SMP - Changed prototype of sys_schedule()
- sys_schedule can change only selected values, -1 means that the
  current value should be kept unchanged. For instance we mostly want
  to change the scheduling quantum and priority but we want to keep
  the process at the current cpu

- RS can hand off its processes to scheduler

- service can read the destination cpu from system.conf

- RS can pass the information farther
2010-09-15 14:10:42 +00:00

112 lines
3.4 KiB
C

#include "pm.h"
#include <assert.h>
#include <minix/callnr.h>
#include <minix/com.h>
#include <minix/config.h>
#include <minix/sched.h>
#include <minix/sysinfo.h>
#include <minix/type.h>
#include <machine/archtypes.h>
#include <lib.h>
#include "mproc.h"
#include <machine/archtypes.h>
#include <timers.h>
#include "kernel/proc.h"
/*===========================================================================*
* init_scheduling *
*===========================================================================*/
PUBLIC void sched_init(void)
{
struct mproc *trmp;
endpoint_t parent_e;
int proc_nr, s;
for (proc_nr=0, trmp=mproc; proc_nr < NR_PROCS; proc_nr++, trmp++) {
/* Don't take over system processes. When the system starts,
* init is blocked on RTS_NO_QUANTUM until PM assigns a
* scheduler, from which other. Given that all other user
* processes are forked from init and system processes are
* managed by RS, there should be no other process that needs
* to be assigned a scheduler here */
if (trmp->mp_flags & IN_USE && !(trmp->mp_flags & PRIV_PROC)) {
assert(_ENDPOINT_P(trmp->mp_endpoint) == INIT_PROC_NR);
parent_e = mproc[trmp->mp_parent].mp_endpoint;
assert(parent_e == trmp->mp_endpoint);
s = sched_start(SCHED_PROC_NR, /* scheduler_e */
trmp->mp_endpoint, /* schedulee_e */
parent_e, /* parent_e */
USER_Q, /* maxprio */
USER_QUANTUM, /* quantum */
-1, /* don't change cpu */
&trmp->mp_scheduler); /* *newsched_e */
if (s != OK) {
printf("PM: SCHED denied taking over scheduling of %s: %d\n",
trmp->mp_name, s);
}
}
}
}
/*===========================================================================*
* sched_start_user *
*===========================================================================*/
PUBLIC int sched_start_user(endpoint_t ep, struct mproc *rmp)
{
unsigned maxprio;
endpoint_t inherit_from;
int rv;
/* convert nice to priority */
if ((rv = nice_to_priority(rmp->mp_nice, &maxprio)) != OK) {
return rv;
}
/* scheduler must know the parent, which is not the case for a child
* of a system process created by a regular fork; in this case the
* scheduler should inherit settings from init rather than the real
* parent
*/
if (mproc[rmp->mp_parent].mp_flags & PRIV_PROC) {
assert(mproc[rmp->mp_parent].mp_scheduler == NONE);
inherit_from = INIT_PROC_NR;
} else {
inherit_from = mproc[rmp->mp_parent].mp_endpoint;
}
/* inherit quantum */
return sched_inherit(ep, /* scheduler_e */
rmp->mp_endpoint, /* schedulee_e */
inherit_from, /* parent_e */
maxprio, /* maxprio */
&rmp->mp_scheduler); /* *newsched_e */
}
/*===========================================================================*
* sched_nice *
*===========================================================================*/
PUBLIC int sched_nice(struct mproc *rmp, int nice)
{
int rv;
message m;
unsigned maxprio;
/* If the kernel is the scheduler, we don't allow messing with the
* priority. If you want to control process priority, assign the process
* to a user-space scheduler */
if (rmp->mp_scheduler == KERNEL || rmp->mp_scheduler == NONE)
return (EINVAL);
if ((rv = nice_to_priority(nice, &maxprio)) != OK) {
return rv;
}
m.SCHEDULING_ENDPOINT = rmp->mp_endpoint;
m.SCHEDULING_MAXPRIO = (int) maxprio;
if ((rv = _taskcall(rmp->mp_scheduler, SCHEDULING_SET_NICE, &m))) {
return rv;
}
return (OK);
}