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);
122 sched_user_prio(td, PUSER);
124 /* Delay putting it on the run queue until now. */
125 if (!(flags & RFSTOPPED))
126 sched_add(td, SRQ_BORING);
133 kproc_exit(int ecode)
142 * Reparent curthread from proc0 to init so that the zombie
145 sx_xlock(&proctree_lock);
147 proc_reparent(p, initproc);
149 sx_xunlock(&proctree_lock);
152 * Wakeup anyone waiting for us to exit.
157 exit1(td, W_EXITCODE(ecode, 0));
161 * Advise a kernel process to suspend (or resume) in its main loop.
162 * Participation is voluntary.
165 kproc_suspend(struct proc *p, int timo)
168 * Make sure this is indeed a system process and we can safely
169 * use the p_siglist field.
172 if ((p->p_flag & P_KTHREAD) == 0) {
176 SIGADDSET(p->p_siglist, SIGSTOP);
178 return msleep(&p->p_siglist, &p->p_mtx, PPAUSE | PDROP, "suspkp", timo);
182 kproc_resume(struct proc *p)
185 * Make sure this is indeed a system process and we can safely
186 * use the p_siglist field.
189 if ((p->p_flag & P_KTHREAD) == 0) {
193 SIGDELSET(p->p_siglist, SIGSTOP);
195 wakeup(&p->p_siglist);
200 kproc_suspend_check(struct proc *p)
203 while (SIGISMEMBER(p->p_siglist, SIGSTOP)) {
204 wakeup(&p->p_siglist);
205 msleep(&p->p_siglist, &p->p_mtx, PPAUSE, "kpsusp", 0);
212 * Start a kernel thread.
214 * This function is used to start "internal" daemons and intended
215 * to be called from SYSINIT().
222 const struct kthread_desc *kp = udata;
225 error = kthread_add((void (*)(void *))kp->func, NULL,
226 NULL, kp->global_threadpp, 0, 0, "%s", kp->arg0);
228 panic("kthread_start: %s: error %d", kp->arg0, error);
232 * Create a kernel thread. It shares its address space
233 * with proc0 - ie: kernel only.
235 * func is the function to start.
236 * arg is the parameter to pass to function on first startup.
237 * newtdp is the return value pointing to the thread's struct thread.
238 * ** XXX fix this --> flags are flags to fork1 (in unistd.h)
239 * fmt and following will be *printf'd into (*newtd)->td_name (for ps, etc.).
242 kthread_add(void (*func)(void *), void *arg, struct proc *p,
243 struct thread **newtdp, int flags, int pages, const char *fmt, ...)
246 struct thread *newtd, *oldtd;
249 panic("kthread_add called too soon");
251 /* If no process supplied, put it on proc0 */
256 oldtd = FIRST_THREAD_IN_PROC(p);
259 /* Initialize our new td */
260 newtd = thread_alloc(pages);
264 bzero(&newtd->td_startzero,
265 __rangeof(struct thread, td_startzero, td_endzero));
266 bzero(&newtd->td_rux, sizeof(newtd->td_rux));
267 newtd->td_map_def_user = NULL;
268 /* XXX check if we should zero. */
269 bcopy(&oldtd->td_startcopy, &newtd->td_startcopy,
270 __rangeof(struct thread, td_startcopy, td_endcopy));
272 /* set up arg0 for 'ps', et al */
274 vsnprintf(newtd->td_name, sizeof(newtd->td_name), fmt, ap);
277 newtd->td_proc = p; /* needed for cpu_set_upcall */
279 /* XXX optimise this probably? */
280 /* On x86 (and probably the others too) it is way too full of junk */
281 /* Needs a better name */
282 cpu_set_upcall(newtd, oldtd);
283 /* put the designated function(arg) as the resume context */
284 cpu_set_fork_handler(newtd, func, arg);
286 newtd->td_pflags |= TDP_KTHREAD;
287 newtd->td_ucred = crhold(p->p_ucred);
289 /* this code almost the same as create_thread() in kern_thr.c */
291 p->p_flag |= P_HADTHREADS;
292 newtd->td_sigmask = oldtd->td_sigmask; /* XXX dubious */
293 thread_link(newtd, p);
295 /* let the scheduler know about these things. */
296 sched_fork_thread(oldtd, newtd);
297 TD_SET_CAN_RUN(newtd);
298 thread_unlock(oldtd);
302 /* Delay putting it on the run queue until now. */
303 if (!(flags & RFSTOPPED)) {
305 sched_add(newtd, SRQ_BORING);
306 thread_unlock(newtd);
318 /* A module may be waiting for us to exit. */
322 * We could rely on thread_exit to call exit1() but
323 * there is extra work that needs to be done
325 if (curthread->td_proc->p_numthreads == 1)
326 kproc_exit(0); /* never returns */
328 p = curthread->td_proc;
335 * Advise a kernel process to suspend (or resume) in its main loop.
336 * Participation is voluntary.
339 kthread_suspend(struct thread *td, int timo)
341 if ((td->td_pflags & TDP_KTHREAD) == 0) {
345 td->td_flags |= TDF_KTH_SUSP;
348 * If it's stopped for some other reason,
349 * kick it to notice our request
350 * or we'll end up timing out
352 wakeup(td); /* traditional place for kernel threads to sleep on */ /* XXX ?? */
353 return (tsleep(&td->td_flags, PPAUSE | PDROP, "suspkt", timo));
357 * let the kthread it can keep going again.
360 kthread_resume(struct thread *td)
362 if ((td->td_pflags & TDP_KTHREAD) == 0) {
366 td->td_flags &= ~TDF_KTH_SUSP;
368 wakeup(&td->td_name);
373 * Used by the thread to poll as to whether it should yield/sleep
374 * and notify the caller that is has happened.
377 kthread_suspend_check(struct thread *td)
379 while (td->td_flags & TDF_KTH_SUSP) {
381 * let the caller know we got the message then sleep
383 wakeup(&td->td_flags);
384 tsleep(&td->td_name, PPAUSE, "ktsusp", 0);
389 kproc_kthread_add(void (*func)(void *), void *arg,
390 struct proc **procptr, struct thread **tdptr,
391 int flags, int pages, const char *procname, const char *fmt, ...)
399 error = kproc_create(func, arg,
400 procptr, flags, pages, "%s", procname);
403 td = FIRST_THREAD_IN_PROC(*procptr);
407 vsnprintf(td->td_name, sizeof(td->td_name), fmt, ap);
412 vsnprintf(buf, sizeof(buf), fmt, ap);
414 error = kthread_add(func, arg, *procptr,
415 tdptr, flags, pages, "%s", buf);