minix/kernel/system/do_schedctl.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

46 lines
1.2 KiB
C

#include "kernel/system.h"
#include <minix/endpoint.h>
/*===========================================================================*
* do_schedctl *
*===========================================================================*/
PUBLIC int do_schedctl(struct proc * caller, message * m_ptr)
{
struct proc *p;
unsigned flags;
int priority, quantum, cpu;
int proc_nr;
int r;
/* check parameter validity */
flags = (unsigned) m_ptr->SCHEDCTL_FLAGS;
if (flags & ~SCHEDCTL_FLAG_KERNEL) {
printf("do_schedctl: flags 0x%x invalid, caller=%d\n",
flags, caller - proc);
return EINVAL;
}
if (!isokendpt(m_ptr->SCHEDCTL_ENDPOINT, &proc_nr))
return EINVAL;
p = proc_addr(proc_nr);
if ((flags & SCHEDCTL_FLAG_KERNEL) == SCHEDCTL_FLAG_KERNEL) {
/* the kernel becomes the scheduler and starts
* scheduling the process.
*/
priority = (int) m_ptr->SCHEDCTL_PRIORITY;
quantum = (int) m_ptr->SCHEDCTL_QUANTUM;
cpu = (int) m_ptr->SCHEDCTL_CPU;
/* Try to schedule the process. */
if((r = sched_proc(p, priority, quantum, cpu) != OK))
return r;
p->p_scheduler = NULL;
} else {
/* the caller becomes the scheduler */
p->p_scheduler = caller;
}
return(OK);
}