/*===========================================================================*
* schedcheck *
*===========================================================================*/
PUBLIC struct proc * schedcheck(void)
{
/* This function is called an instant before proc_ptr is
* to be scheduled again.
*/
NOREC_ENTER(schedch);
vmassert(intr_disabled());
/*
* if the current process is still runnable check the misc flags and let
* it run unless it becomes not runnable in the meantime
*/
if (proc_is_runnable(proc_ptr))
goto check_misc_flags;
/*
* if a process becomes not runnable while handling the misc flags, we
* need to pick a new one here and start from scratch. Also if the
* current process wasn' runnable, we pick a new one here
*/
not_runnable_pick_new:
if (proc_is_preempted(proc_ptr)) {
proc_ptr->p_rts_flags &= ~RTS_PREEMPTED;
if (proc_is_runnable(proc_ptr))
enqueue_head(proc_ptr);
}
/* this enqueues the process again */
if (proc_no_quantum(proc_ptr))
RTS_UNSET(proc_ptr, RTS_NO_QUANTUM);
/*
* if we have no process to run, set IDLE as the current process for
* time accounting and put the cpu in and idle state. After the next
* timer interrupt the execution resumes here and we can pick another
* process. If there is still nothing runnable we "schedule" IDLE again
*/
while( !(proc_ptr = pick_proc())) {
proc_ptr = proc_addr(IDLE);
if (priv(proc_ptr)->s_flags & BILLABLE)
bill_ptr = proc_ptr;
idle();
}
check_misc_flags:
vmassert(proc_ptr);
vmassert(proc_is_runnable(proc_ptr));
while (proc_ptr->p_misc_flags &
(MF_DELIVERMSG | MF_SC_DEFER | MF_SC_TRACE | MF_SC_ACTIVE)) {
vmassert(proc_is_runnable(proc_ptr));
if (proc_ptr->p_misc_flags & MF_DELIVERMSG) {
TRACE(VF_SCHEDULING, printf("delivering to %s / %d\n",
proc_ptr->p_name, proc_ptr->p_endpoint););
if(delivermsg(proc_ptr) == VMSUSPEND) {
TRACE(VF_SCHEDULING,
printf("suspending %s / %d\n",
proc_ptr->p_name,
proc_ptr->p_endpoint););
PUBLIC void vm_set_cr3(struct proc *newptproc)
{
int u = 0;
if(!intr_disabled()) { lock; u = 1; }
vm_cr3= newptproc->p_seg.p_cr3;
if(vm_cr3) {
level0(set_cr3);
ptproc = newptproc;
}
if(u) { unlock; }
}