2 * Copyright (C) 2000-2004 The FreeBSD Project. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/kthread.h>
34 #include <sys/mutex.h>
36 #include <sys/resourcevar.h>
37 #include <sys/sched.h>
38 #include <sys/unistd.h>
43 static void idle_setup(void *dummy);
44 SYSINIT(idle_setup, SI_SUB_SCHED_IDLE, SI_ORDER_FIRST, idle_setup, NULL)
46 static void idle_proc(void *dummy);
49 * Set up per-cpu idle process contexts. The AP's shouldn't be running or
50 * accessing their idle processes at this point, so don't bother with
54 idle_setup(void *dummy)
64 SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
65 error = kthread_create(idle_proc, NULL, &p,
66 RFSTOPPED | RFHIGHPID, 0, "idle: cpu%d", pc->pc_cpuid);
67 pc->pc_idlethread = FIRST_THREAD_IN_PROC(p);
69 error = kthread_create(idle_proc, NULL, &p,
70 RFSTOPPED | RFHIGHPID, 0, "idle");
71 PCPU_SET(idlethread, FIRST_THREAD_IN_PROC(p));
74 panic("idle_setup: kthread_create error %d\n", error);
77 p->p_flag |= P_NOLOAD;
78 mtx_lock_spin(&sched_lock);
79 td = FIRST_THREAD_IN_PROC(p);
81 td->td_flags |= TDF_IDLETD;
82 sched_class(td->td_ksegrp, PRI_IDLE);
83 sched_prio(td, PRI_MAX_IDLE);
84 mtx_unlock_spin(&sched_lock);
92 * The actual idle process.
95 idle_proc(void *dummy)
106 mycpu = PCPU_GET(cpumask);
107 mtx_lock_spin(&sched_lock);
108 idle_cpus_mask |= mycpu;
109 mtx_unlock_spin(&sched_lock);
112 mtx_assert(&Giant, MA_NOTOWNED);
114 while (sched_runnable() == 0)
117 mtx_lock_spin(&sched_lock);
119 idle_cpus_mask &= ~mycpu;
121 mi_switch(SW_VOL, NULL);
123 idle_cpus_mask |= mycpu;
125 mtx_unlock_spin(&sched_lock);