xref: /minix3/minix/kernel/system/do_schedctl.c (revision 433d6423c39e34ec4b79c950597bb2d236f886be)
1*433d6423SLionel Sambuc #include "kernel/system.h"
2*433d6423SLionel Sambuc #include <minix/endpoint.h>
3*433d6423SLionel Sambuc 
4*433d6423SLionel Sambuc /*===========================================================================*
5*433d6423SLionel Sambuc  *			          do_schedctl			     *
6*433d6423SLionel Sambuc  *===========================================================================*/
7*433d6423SLionel Sambuc int do_schedctl(struct proc * caller, message * m_ptr)
8*433d6423SLionel Sambuc {
9*433d6423SLionel Sambuc 	struct proc *p;
10*433d6423SLionel Sambuc 	uint32_t flags;
11*433d6423SLionel Sambuc 	int priority, quantum, cpu;
12*433d6423SLionel Sambuc 	int proc_nr;
13*433d6423SLionel Sambuc 	int r;
14*433d6423SLionel Sambuc 
15*433d6423SLionel Sambuc 	/* check parameter validity */
16*433d6423SLionel Sambuc 	flags = m_ptr->m_lsys_krn_schedctl.flags;
17*433d6423SLionel Sambuc 	if (flags & ~SCHEDCTL_FLAG_KERNEL) {
18*433d6423SLionel Sambuc 		printf("do_schedctl: flags 0x%x invalid, caller=%d\n",
19*433d6423SLionel Sambuc 			flags, caller - proc);
20*433d6423SLionel Sambuc 		return EINVAL;
21*433d6423SLionel Sambuc 	}
22*433d6423SLionel Sambuc 
23*433d6423SLionel Sambuc 	if (!isokendpt(m_ptr->m_lsys_krn_schedctl.endpoint, &proc_nr))
24*433d6423SLionel Sambuc 		return EINVAL;
25*433d6423SLionel Sambuc 
26*433d6423SLionel Sambuc 	p = proc_addr(proc_nr);
27*433d6423SLionel Sambuc 
28*433d6423SLionel Sambuc 	if ((flags & SCHEDCTL_FLAG_KERNEL) == SCHEDCTL_FLAG_KERNEL) {
29*433d6423SLionel Sambuc 		/* the kernel becomes the scheduler and starts
30*433d6423SLionel Sambuc 		 * scheduling the process.
31*433d6423SLionel Sambuc 		 */
32*433d6423SLionel Sambuc 		priority = m_ptr->m_lsys_krn_schedctl.priority;
33*433d6423SLionel Sambuc 		quantum = m_ptr->m_lsys_krn_schedctl.quantum;
34*433d6423SLionel Sambuc 		cpu = m_ptr->m_lsys_krn_schedctl.cpu;
35*433d6423SLionel Sambuc 
36*433d6423SLionel Sambuc 		/* Try to schedule the process. */
37*433d6423SLionel Sambuc 		if((r = sched_proc(p, priority, quantum, cpu) != OK))
38*433d6423SLionel Sambuc 			return r;
39*433d6423SLionel Sambuc 		p->p_scheduler = NULL;
40*433d6423SLionel Sambuc 	} else {
41*433d6423SLionel Sambuc 		/* the caller becomes the scheduler */
42*433d6423SLionel Sambuc 		p->p_scheduler = caller;
43*433d6423SLionel Sambuc 	}
44*433d6423SLionel Sambuc 
45*433d6423SLionel Sambuc 	return(OK);
46*433d6423SLionel Sambuc }
47