2 * Copyright (c) 1999 Peter Wemm <peter@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/sys/kern/kern_kthread.c,v 1.5.2.3 2001/12/25 01:51:14 dillon Exp $
27 * $DragonFly: src/sys/kern/kern_kthread.c,v 1.13 2006/12/18 20:41:01 dillon Exp $
30 #include <sys/param.h>
31 #include <sys/systm.h>
33 #include <sys/kthread.h>
34 #include <sys/ptrace.h>
35 #include <sys/resourcevar.h>
36 #include <sys/signalvar.h>
37 #include <sys/unistd.h>
40 #include <machine/stdarg.h>
42 static struct lwkt_token kpsus_token = LWKT_TOKEN_INITIALIZER(kpsus_token);
46 * Create a kernel process/thread/whatever. It shares it's address space
47 * with proc0 - ie: kernel only. 5.x compatible.
49 * All kthreads are created as MPSAFE threads.
52 kthread_create(void (*func)(void *), void *arg,
53 struct thread **tdp, const char *fmt, ...)
58 td = lwkt_alloc_thread(NULL, LWKT_THREAD_STACK, -1, TDF_VERBOSE);
61 cpu_set_thread_handler(td, kthread_exit, func, arg);
64 * Set up arg0 for 'ps' etc
67 kvsnprintf(td->td_comm, sizeof(td->td_comm), fmt, ap);
70 td->td_ucred = crhold(proc0.p_ucred);
73 * Schedule the thread to run
80 kthread_create_cpu(void (*func)(void *), void *arg,
81 struct thread **tdp, int cpu, const char *fmt, ...)
86 td = lwkt_alloc_thread(NULL, LWKT_THREAD_STACK, cpu, TDF_VERBOSE);
89 cpu_set_thread_handler(td, kthread_exit, func, arg);
92 * Set up arg0 for 'ps' etc
95 kvsnprintf(td->td_comm, sizeof(td->td_comm), fmt, ap);
98 td->td_ucred = crhold(proc0.p_ucred);
101 * Schedule the thread to run
109 * Same as kthread_create() but you can specify a custom stack size.
112 kthread_create_stk(void (*func)(void *), void *arg,
113 struct thread **tdp, int stksize, const char *fmt, ...)
118 td = lwkt_alloc_thread(NULL, stksize, -1, TDF_VERBOSE);
121 cpu_set_thread_handler(td, kthread_exit, func, arg);
124 kvsnprintf(td->td_comm, sizeof(td->td_comm), fmt, ap);
133 * Destroy an LWKT thread. Warning! This function is not called when
134 * a process exits, cpu_proc_exit() directly calls cpu_thread_exit() and
135 * uses a different reaping mechanism.
137 * XXX duplicates lwkt_exit()
146 * Start a kernel process. This is called after a fork() call in
147 * mi_startup() in the file kern/init_main.c.
149 * This function is used to start "internal" daemons and intended
150 * to be called from SYSINIT().
152 * These threads are created MPSAFE.
155 kproc_start(const void *udata)
157 const struct kproc_desc *kp = udata;
160 error = kthread_create((void (*)(void *))kp->func, NULL,
161 kp->global_threadpp, kp->arg0);
162 lwkt_setpri(*kp->global_threadpp, TDPRI_KERN_DAEMON);
164 panic("kproc_start: %s: error %d", kp->arg0, error);
168 * Advise a kernel process to suspend (or resume) in its main loop.
169 * Participation is voluntary.
172 suspend_kproc(struct thread *td, int timo)
174 if (td->td_proc == NULL) {
175 lwkt_gettoken(&kpsus_token);
176 /* request thread pause */
177 atomic_set_int(&td->td_mpflags, TDF_MP_STOPREQ);
179 while (td->td_mpflags & TDF_MP_STOPREQ) {
180 int error = tsleep(td, 0, "suspkp", timo);
181 if (error == EWOULDBLOCK)
184 atomic_clear_int(&td->td_mpflags, TDF_MP_STOPREQ);
185 lwkt_reltoken(&kpsus_token);
188 return(EINVAL); /* not a kernel thread */
193 kproc_suspend_loop(void)
195 struct thread *td = curthread;
197 if (td->td_mpflags & TDF_MP_STOPREQ) {
198 lwkt_gettoken(&kpsus_token);
199 atomic_clear_int(&td->td_mpflags, TDF_MP_STOPREQ);
200 while ((td->td_mpflags & TDF_MP_WAKEREQ) == 0) {
202 tsleep(td, 0, "kpsusp", 0);
204 atomic_clear_int(&td->td_mpflags, TDF_MP_WAKEREQ);
206 lwkt_reltoken(&kpsus_token);