kern_kthread.c revision 55722
148391Speter/* 248391Speter * Copyright (c) 1999 Peter Wemm <peter@FreeBSD.org> 348391Speter * All rights reserved. 448391Speter * 548391Speter * Redistribution and use in source and binary forms, with or without 648391Speter * modification, are permitted provided that the following conditions 748391Speter * are met: 848391Speter * 1. Redistributions of source code must retain the above copyright 948391Speter * notice, this list of conditions and the following disclaimer. 1048391Speter * 2. Redistributions in binary form must reproduce the above copyright 1148391Speter * notice, this list of conditions and the following disclaimer in the 1248391Speter * documentation and/or other materials provided with the distribution. 1348391Speter * 1448391Speter * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1548391Speter * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1648391Speter * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1748391Speter * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1848391Speter * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 1948391Speter * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2048391Speter * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2148391Speter * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2248391Speter * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2348391Speter * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2448391Speter * SUCH DAMAGE. 2548391Speter * 2648391Speter * $FreeBSD: head/sys/kern/kern_kthread.c 55722 2000-01-10 08:00:58Z imp $ 2748391Speter */ 2848391Speter 2948391Speter#include <sys/param.h> 3048391Speter#include <sys/systm.h> 3148391Speter#include <sys/proc.h> 3248391Speter#include <sys/kthread.h> 3355722Simp#include <sys/resourcevar.h> 3455539Sluoqi#include <sys/signalvar.h> 3548391Speter#include <sys/unistd.h> 3648391Speter#include <sys/wait.h> 3748391Speter 3848391Speter#include <machine/stdarg.h> 3948391Speter 4048391Speter/* 4148391Speter * Start a kernel process. This is called after a fork() call in 4248391Speter * mi_startup() in the file kern/init_main.c. 4348391Speter * 4448391Speter * This function is used to start "internal" daemons and intended 4548391Speter * to be called from SYSINIT(). 4648391Speter */ 4748391Spetervoid 4848391Speterkproc_start(udata) 4948391Speter const void *udata; 5048391Speter{ 5148391Speter const struct kproc_desc *kp = udata; 5248391Speter int error; 5348391Speter 5448391Speter error = kthread_create((void (*)(void *))kp->func, NULL, 5548391Speter kp->global_procpp, kp->arg0); 5648391Speter if (error) 5748391Speter panic("kproc_start: %s: error %d", kp->arg0, error); 5848391Speter} 5948391Speter 6048391Speter/* 6148391Speter * Create a kernel process/thread/whatever. It shares it's address space 6248391Speter * with proc0 - ie: kernel only. 6348391Speter */ 6448391Speterint 6548391Speterkthread_create(void (*func)(void *), void *arg, 6648391Speter struct proc **newpp, const char *fmt, ...) 6748391Speter{ 6848391Speter int error; 6948391Speter va_list ap; 7048391Speter struct proc *p2; 7148391Speter 7255722Simp if (!proc0.p_stats || proc0.p_stats->p_start.tv_sec == 0) { 7355722Simp panic("kthread_create called too soon"); 7455722Simp } 7555722Simp 7648391Speter error = fork1(&proc0, RFMEM | RFFDG | RFPROC, &p2); 7748391Speter if (error) 7848391Speter return error; 7948391Speter 8048391Speter /* save a global descriptor, if desired */ 8148391Speter if (newpp != NULL) 8248391Speter *newpp = p2; 8348391Speter 8448391Speter /* this is a non-swapped system process */ 8552140Sluoqi p2->p_flag |= P_INMEM | P_SYSTEM; 8652140Sluoqi p2->p_procsig->ps_flag |= PS_NOCLDWAIT; 8748391Speter PHOLD(p2); 8848391Speter 8948391Speter /* set up arg0 for 'ps', et al */ 9048391Speter va_start(ap, fmt); 9148391Speter vsnprintf(p2->p_comm, sizeof(p2->p_comm), fmt, ap); 9248391Speter va_end(ap); 9348391Speter 9448391Speter /* call the processes' main()... */ 9548391Speter cpu_set_fork_handler(p2, func, arg); 9648391Speter 9748391Speter return 0; 9848391Speter} 9948391Speter 10048391Spetervoid 10148391Speterkthread_exit(int ecode) 10248391Speter{ 10348391Speter exit1(curproc, W_EXITCODE(ecode, 0)); 10448391Speter} 10548391Speter 10655539Sluoqi/* 10755539Sluoqi * Advise a kernel process to suspend (or resume) in its main loop. 10855539Sluoqi * Participation is voluntary. 10955539Sluoqi */ 11055539Sluoqiint 11155539Sluoqisuspend_kproc(struct proc *p, int timo) 11255539Sluoqi{ 11355539Sluoqi /* 11455539Sluoqi * Make sure this is indeed a system process and we can safely 11555539Sluoqi * use the p_siglist field. 11655539Sluoqi */ 11755539Sluoqi if ((p->p_flag & P_SYSTEM) == 0) 11855539Sluoqi return (EINVAL); 11955539Sluoqi SIGADDSET(p->p_siglist, SIGSTOP); 12055539Sluoqi return tsleep((caddr_t)&p->p_siglist, PPAUSE, "suspkp", timo); 12155539Sluoqi} 12255539Sluoqi 12355539Sluoqiint 12455539Sluoqiresume_kproc(struct proc *p) 12555539Sluoqi{ 12655539Sluoqi /* 12755539Sluoqi * Make sure this is indeed a system process and we can safely 12855539Sluoqi * use the p_siglist field. 12955539Sluoqi */ 13055539Sluoqi if ((p->p_flag & P_SYSTEM) == 0) 13155539Sluoqi return (EINVAL); 13255539Sluoqi SIGDELSET(p->p_siglist, SIGSTOP); 13355539Sluoqi wakeup((caddr_t)&p->p_siglist); 13455539Sluoqi return (0); 13555539Sluoqi} 13655539Sluoqi 13755539Sluoqivoid 13855539Sluoqikproc_suspend_loop(struct proc *p) 13955539Sluoqi{ 14055539Sluoqi while (SIGISMEMBER(p->p_siglist, SIGSTOP)) { 14155539Sluoqi wakeup((caddr_t)&p->p_siglist); 14255539Sluoqi tsleep((caddr_t)&p->p_siglist, PPAUSE, "kpsusp", 0); 14355539Sluoqi } 14455539Sluoqi} 145