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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kthread.h>
34 #include <sys/mutex.h>
36 #include <sys/resourcevar.h>
37 #include <sys/signalvar.h>
39 #include <sys/unistd.h>
41 #include <sys/sched.h>
43 #include <vm/vm_extern.h>
45 #include <machine/stdarg.h>
48 * Start a kernel process. This is called after a fork() call in
49 * mi_startup() in the file kern/init_main.c.
51 * This function is used to start "internal" daemons and intended
52 * to be called from SYSINIT().
58 const struct kproc_desc *kp = udata;
61 error = kproc_create((void (*)(void *))kp->func, NULL,
62 kp->global_procpp, 0, 0, "%s", kp->arg0);
64 panic("kproc_start: %s: error %d", kp->arg0, error);
68 * Create a kernel process/thread/whatever. It shares its address space
69 * with proc0 - ie: kernel only.
71 * func is the function to start.
72 * arg is the parameter to pass to function on first startup.
73 * newpp is the return value pointing to the thread's struct proc.
74 * flags are flags to fork1 (in unistd.h)
75 * fmt and following will be *printf'd into (*newpp)->p_comm (for ps, etc.).
78 kproc_create(void (*func)(void *), void *arg,
79 struct proc **newpp, int flags, int pages, const char *fmt, ...)
87 panic("kproc_create called too soon");
89 error = fork1(&thread0, RFMEM | RFFDG | RFPROC | RFSTOPPED | flags,
94 /* save a global descriptor, if desired */
98 /* this is a non-swapped system process */
100 td = FIRST_THREAD_IN_PROC(p2);
101 p2->p_flag |= P_SYSTEM | P_KTHREAD;
102 td->td_pflags |= TDP_KTHREAD;
103 mtx_lock(&p2->p_sigacts->ps_mtx);
104 p2->p_sigacts->ps_flag |= PS_NOCLDWAIT;
105 mtx_unlock(&p2->p_sigacts->ps_mtx);
108 /* set up arg0 for 'ps', et al */
110 vsnprintf(p2->p_comm, sizeof(p2->p_comm), fmt, ap);
112 /* set up arg0 for 'ps', et al */
114 vsnprintf(td->td_name, sizeof(td->td_name), fmt, ap);
117 /* call the processes' main()... */
118 cpu_set_fork_handler(td, func, arg);
121 /* Delay putting it on the run queue until now. */
122 if (!(flags & RFSTOPPED)) {
124 sched_add(td, SRQ_BORING);
132 kproc_exit(int ecode)
141 * Reparent curthread from proc0 to init so that the zombie
144 sx_xlock(&proctree_lock);
146 proc_reparent(p, initproc);
148 sx_xunlock(&proctree_lock);
151 * Wakeup anyone waiting for us to exit.
156 exit1(td, W_EXITCODE(ecode, 0));
160 * Advise a kernel process to suspend (or resume) in its main loop.
161 * Participation is voluntary.
164 kproc_suspend(struct proc *p, int timo)
167 * Make sure this is indeed a system process and we can safely
168 * use the p_siglist field.
171 if ((p->p_flag & P_KTHREAD) == 0) {
175 SIGADDSET(p->p_siglist, SIGSTOP);
177 return msleep(&p->p_siglist, &p->p_mtx, PPAUSE | PDROP, "suspkp", timo);
181 kproc_resume(struct proc *p)
184 * Make sure this is indeed a system process and we can safely
185 * use the p_siglist field.
188 if ((p->p_flag & P_KTHREAD) == 0) {
192 SIGDELSET(p->p_siglist, SIGSTOP);
194 wakeup(&p->p_siglist);
199 kproc_suspend_check(struct proc *p)
202 while (SIGISMEMBER(p->p_siglist, SIGSTOP)) {
203 wakeup(&p->p_siglist);
204 msleep(&p->p_siglist, &p->p_mtx, PPAUSE, "kpsusp", 0);
211 * Start a kernel thread.
213 * This function is used to start "internal" daemons and intended
214 * to be called from SYSINIT().
221 const struct kthread_desc *kp = udata;
224 error = kthread_add((void (*)(void *))kp->func, NULL,
225 NULL, kp->global_threadpp, 0, 0, "%s", kp->arg0);
227 panic("kthread_start: %s: error %d", kp->arg0, error);
231 * Create a kernel thread. It shares its address space
232 * with proc0 - ie: kernel only.
234 * func is the function to start.
235 * arg is the parameter to pass to function on first startup.
236 * newtdp is the return value pointing to the thread's struct thread.
237 * ** XXX fix this --> flags are flags to fork1 (in unistd.h)
238 * fmt and following will be *printf'd into (*newtd)->td_name (for ps, etc.).
241 kthread_add(void (*func)(void *), void *arg, struct proc *p,
242 struct thread **newtdp, int flags, int pages, const char *fmt, ...)
245 struct thread *newtd, *oldtd;
248 panic("kthread_add called too soon");
250 /* If no process supplied, put it on proc0 */
255 oldtd = FIRST_THREAD_IN_PROC(p);
258 /* Initialize our new td */
259 newtd = thread_alloc(pages);
263 bzero(&newtd->td_startzero,
264 __rangeof(struct thread, td_startzero, td_endzero));
265 /* XXX check if we should zero. */
266 bcopy(&oldtd->td_startcopy, &newtd->td_startcopy,
267 __rangeof(struct thread, td_startcopy, td_endcopy));
269 /* set up arg0 for 'ps', et al */
271 vsnprintf(newtd->td_name, sizeof(newtd->td_name), fmt, ap);
274 newtd->td_proc = p; /* needed for cpu_set_upcall */
276 /* XXX optimise this probably? */
277 /* On x86 (and probably the others too) it is way too full of junk */
278 /* Needs a better name */
279 cpu_set_upcall(newtd, oldtd);
280 /* put the designated function(arg) as the resume context */
281 cpu_set_fork_handler(newtd, func, arg);
283 newtd->td_pflags |= TDP_KTHREAD;
284 newtd->td_ucred = crhold(p->p_ucred);
286 /* this code almost the same as create_thread() in kern_thr.c */
288 p->p_flag |= P_HADTHREADS;
289 newtd->td_sigmask = oldtd->td_sigmask; /* XXX dubious */
290 thread_link(newtd, p);
292 /* let the scheduler know about these things. */
293 sched_fork_thread(oldtd, newtd);
294 TD_SET_CAN_RUN(newtd);
295 thread_unlock(oldtd);
299 /* Delay putting it on the run queue until now. */
300 if (!(flags & RFSTOPPED)) {
302 sched_add(newtd, SRQ_BORING);
303 thread_unlock(newtd);
315 /* A module may be waiting for us to exit. */
319 * We could rely on thread_exit to call exit1() but
320 * there is extra work that needs to be done
322 if (curthread->td_proc->p_numthreads == 1)
323 kproc_exit(0); /* never returns */
325 p = curthread->td_proc;
332 * Advise a kernel process to suspend (or resume) in its main loop.
333 * Participation is voluntary.
336 kthread_suspend(struct thread *td, int timo)
338 if ((td->td_pflags & TDP_KTHREAD) == 0) {
342 td->td_flags |= TDF_KTH_SUSP;
345 * If it's stopped for some other reason,
346 * kick it to notice our request
347 * or we'll end up timing out
349 wakeup(td); /* traditional place for kernel threads to sleep on */ /* XXX ?? */
350 return (tsleep(&td->td_flags, PPAUSE | PDROP, "suspkt", timo));
354 * let the kthread it can keep going again.
357 kthread_resume(struct thread *td)
359 if ((td->td_pflags & TDP_KTHREAD) == 0) {
363 td->td_flags &= ~TDF_KTH_SUSP;
365 wakeup(&td->td_name);
370 * Used by the thread to poll as to whether it should yield/sleep
371 * and notify the caller that is has happened.
374 kthread_suspend_check(struct thread *td)
376 while (td->td_flags & TDF_KTH_SUSP) {
378 * let the caller know we got the message then sleep
380 wakeup(&td->td_flags);
381 tsleep(&td->td_name, PPAUSE, "ktsusp", 0);
386 kproc_kthread_add(void (*func)(void *), void *arg,
387 struct proc **procptr, struct thread **tdptr,
388 int flags, int pages, char * procname, const char *fmt, ...)
396 error = kproc_create(func, arg,
397 procptr, flags, pages, "%s", procname);
400 td = FIRST_THREAD_IN_PROC(*procptr);
404 vsnprintf(td->td_name, sizeof(td->td_name), fmt, ap);
409 vsnprintf(buf, sizeof(buf), fmt, ap);
411 error = kthread_add(func, arg, *procptr,
412 tdptr, flags, pages, "%s", buf);