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/*-
* Copyright (c) 2000, All rights reserved. See /usr/src/COPYRIGHT
*
* $FreeBSD$
*/
#include "opt_ktrace.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/smp.h>
#include <sys/unistd.h>
#ifdef KTRACE
#include <sys/uio.h>
#include <sys/ktrace.h>
#endif
static void idle_setup(void *dummy);
SYSINIT(idle_setup, SI_SUB_SCHED_IDLE, SI_ORDER_FIRST, idle_setup, NULL)
static void idle_proc(void *dummy);
/*
* Setup per-cpu idle process contexts. The AP's shouldn't be running or
* accessing their idle processes at this point, so don't bother with
* locking.
*/
static void
idle_setup(void *dummy)
{
#ifdef SMP
struct pcpu *pc;
#endif
struct proc *p;
int error;
#ifdef SMP
SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
error = kthread_create(idle_proc, NULL, &p,
RFSTOPPED | RFHIGHPID, "idle: cpu%d", pc->pc_cpuid);
pc->pc_idlethread = &p->p_thread;
if (pc->pc_curthread == NULL) {
pc->pc_curthread = pc->pc_idlethread;
pc->pc_idlethread->td_critnest = 0;
}
#else
error = kthread_create(idle_proc, NULL, &p,
RFSTOPPED | RFHIGHPID, "idle");
PCPU_SET(idlethread, &p->p_thread);
#endif
if (error)
panic("idle_setup: kthread_create error %d\n", error);
p->p_flag |= P_NOLOAD;
p->p_stat = SRUN;
#ifdef SMP
}
#endif
}
/*
* idle process context
*/
static void
idle_proc(void *dummy)
{
#ifdef DIAGNOSTIC
int count;
#endif
for (;;) {
mtx_assert(&Giant, MA_NOTOWNED);
#ifdef DIAGNOSTIC
count = 0;
while (count >= 0 && procrunnable() == 0) {
#else
while (procrunnable() == 0) {
#endif
/*
* This is a good place to put things to be done in
* the background, including sanity checks.
*/
#ifdef DIAGNOSTIC
if (count++ < 0)
CTR0(KTR_PROC, "idle_proc: timed out waiting"
" for a process");
#endif
#ifdef __i386__
cpu_idle();
#endif
}
mtx_lock_spin(&sched_lock);
curproc->p_stats->p_ru.ru_nvcsw++;
mi_switch();
mtx_unlock_spin(&sched_lock);
}
}
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