1 /* $OpenBSD: kern_kthread.c,v 1.3 1999/01/26 23:07:26 niklas Exp $ */ 2 /* $NetBSD: kern_kthread.c,v 1.3 1998/12/22 21:21:36 kleink Exp $ */ 3 4 /*- 5 * Copyright (c) 1998 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 10 * NASA Ames Research Center. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the NetBSD 23 * Foundation, Inc. and its contributors. 24 * 4. Neither the name of The NetBSD Foundation nor the names of its 25 * contributors may be used to endorse or promote products derived 26 * from this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 29 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 30 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 31 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 32 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 33 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 34 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 35 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 36 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 37 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 38 * POSSIBILITY OF SUCH DAMAGE. 39 */ 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/kthread.h> 45 #include <sys/proc.h> 46 #include <sys/wait.h> 47 #include <sys/malloc.h> 48 #include <sys/queue.h> 49 50 #include <machine/cpu.h> 51 52 /* 53 * note that stdarg.h and the ansi style va_start macro is used for both 54 * ansi and traditional c complers. 55 * XXX: this requires that stdarg.h define: va_alist and va_dcl 56 */ 57 #include <machine/stdarg.h> 58 59 /* 60 * Fork a kernel thread. Any process can request this to be done. 61 * The VM space and limits, etc. will be shared with proc0. 62 */ 63 int 64 #if __STDC__ 65 kthread_create(void (*func)(void *), void *arg, 66 struct proc **newpp, const char *fmt, ...) 67 #else 68 kthread_create(func, arg, newpp, fmt, va_alist) 69 void (*func) __P((void *)); 70 void *arg; 71 struct proc **newpp; 72 const char *fmt; 73 va_dcl 74 #endif 75 { 76 struct proc *p2; 77 register_t rv[2]; 78 int error; 79 va_list ap; 80 81 /* 82 * First, create the new process. Share the memory, copy file 83 * descriptors and don't leave the exit status around for the 84 * parent to wait for. 85 */ 86 error = fork1(&proc0, ISRFORK, RFPROC | RFMEM | RFFDG | RFNOWAIT, rv); 87 if (error) 88 return (error); 89 90 #ifdef cpu_set_init_frame /* XXX should go away */ 91 if (rv[1]) { 92 /* 93 * Now in child. 94 */ 95 func(arg); 96 return (0); 97 } 98 #endif 99 100 p2 = pfind(rv[0]); 101 102 #ifndef cpu_set_init_frame /* XXX should go away */ 103 /* Arrange for it to start at the specified function. */ 104 cpu_set_kpc(p2, func, arg); 105 #endif 106 107 /* 108 * Mark it as a system process and not a candidate for 109 * swapping. 110 */ 111 p2->p_flag |= P_INMEM | P_SYSTEM; /* XXX */ 112 113 /* Name it as specified. */ 114 va_start(ap, fmt); 115 vsprintf(p2->p_comm, fmt, ap); 116 va_end(ap); 117 118 /* All done! */ 119 if (newpp != NULL) 120 *newpp = p2; 121 return (0); 122 } 123 124 /* 125 * Cause a kernel thread to exit. Assumes the exiting thread is the 126 * current context. 127 */ 128 void 129 kthread_exit(ecode) 130 int ecode; 131 { 132 133 /* 134 * XXX What do we do with the exit code? Should we even bother 135 * XXX with it? The parent (proc0) isn't going to do much with 136 * XXX it. 137 */ 138 if (ecode != 0) 139 printf("WARNING: thread `%s' (%d) exits with status %d\n", 140 curproc->p_comm, curproc->p_pid, ecode); 141 142 exit1(curproc, W_EXITCODE(ecode, 0)); 143 144 /* 145 * XXX Fool the compiler. Making exit1() __noreturn__ is a can 146 * XXX of worms right now. 147 */ 148 for (;;); 149 } 150 151 struct kthread_q { 152 SIMPLEQ_ENTRY(kthread_q) kq_q; 153 void (*kq_func) __P((void *)); 154 void *kq_arg; 155 }; 156 157 SIMPLEQ_HEAD(, kthread_q) kthread_q = SIMPLEQ_HEAD_INITIALIZER(kthread_q); 158 159 /* 160 * Defer the creation of a kernel thread. Once the standard kernel threads 161 * and processes have been created, this queue will be run to callback to 162 * the caller to create threads for e.g. file systems and device drivers. 163 */ 164 void 165 kthread_create_deferred(func, arg) 166 void (*func) __P((void *)); 167 void *arg; 168 { 169 struct kthread_q *kq; 170 171 kq = malloc(sizeof *kq, M_TEMP, M_NOWAIT); 172 if (kq == NULL) 173 panic("unable to allocate kthread_q"); 174 bzero(kq, sizeof *kq); 175 176 kq->kq_func = func; 177 kq->kq_arg = arg; 178 179 SIMPLEQ_INSERT_TAIL(&kthread_q, kq, kq_q); 180 } 181 182 void 183 kthread_run_deferred_queue() 184 { 185 struct kthread_q *kq; 186 187 while ((kq = SIMPLEQ_FIRST(&kthread_q)) != NULL) { 188 SIMPLEQ_REMOVE_HEAD(&kthread_q, kq, kq_q); 189 (*kq->kq_func)(kq->kq_arg); 190 free(kq, M_TEMP); 191 } 192 } 193