thr_create.c revision 53847
1/* 2 * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by John Birrell. 16 * 4. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD: head/lib/libkse/thread/thr_create.c 53847 1999-11-28 19:47:43Z dfr $ 33 */ 34#include <errno.h> 35#include <stdlib.h> 36#include <string.h> 37#include <fcntl.h> 38#include <unistd.h> 39#include <stddef.h> 40#include <sys/time.h> 41#include <sys/param.h> 42#include <sys/mman.h> 43#ifdef _THREAD_SAFE 44#include <machine/reg.h> 45#include <pthread.h> 46#include "pthread_private.h" 47#include "libc_private.h" 48 49static u_int64_t next_uniqueid = 1; 50 51#define OFF(f) offsetof(struct pthread, f) 52int _thread_next_offset = OFF(tle.tqe_next); 53int _thread_uniqueid_offset = OFF(uniqueid); 54int _thread_state_offset = OFF(state); 55int _thread_name_offset = OFF(name); 56int _thread_sig_saved_offset = OFF(sig_saved); 57int _thread_saved_sigcontext_offset = OFF(saved_sigcontext); 58int _thread_saved_jmp_buf_offset = OFF(saved_jmp_buf); 59#undef OFF 60 61int _thread_PS_RUNNING_value = PS_RUNNING; 62int _thread_PS_DEAD_value = PS_DEAD; 63 64int 65pthread_create(pthread_t * thread, const pthread_attr_t * attr, 66 void *(*start_routine) (void *), void *arg) 67{ 68 int f_gc = 0; 69 int ret = 0; 70 pthread_t gc_thread; 71 pthread_t new_thread; 72 pthread_attr_t pattr; 73 void *stack; 74 75 /* 76 * Locking functions in libc are required when there are 77 * threads other than the initial thread. 78 */ 79 __isthreaded = 1; 80 81 /* Allocate memory for the thread structure: */ 82 if ((new_thread = (pthread_t) malloc(sizeof(struct pthread))) == NULL) { 83 /* Insufficient memory to create a thread: */ 84 ret = EAGAIN; 85 } else { 86 /* Check if default thread attributes are required: */ 87 if (attr == NULL || *attr == NULL) { 88 /* Use the default thread attributes: */ 89 pattr = &pthread_attr_default; 90 } else { 91 pattr = *attr; 92 } 93 /* Check if a stack was specified in the thread attributes: */ 94 if ((stack = pattr->stackaddr_attr) != NULL) { 95 } 96 /* Allocate memory for a default-size stack: */ 97 else if (pattr->stacksize_attr == PTHREAD_STACK_DEFAULT) { 98 struct stack *spare_stack; 99 100 /* Allocate or re-use a default-size stack. */ 101 102 /* 103 * Use the garbage collector mutex for synchronization 104 * of the spare stack list. 105 */ 106 if (pthread_mutex_lock(&_gc_mutex) != 0) 107 PANIC("Cannot lock gc mutex"); 108 109 if ((spare_stack = SLIST_FIRST(&_stackq)) != NULL) { 110 /* Use the spare stack. */ 111 SLIST_REMOVE_HEAD(&_stackq, qe); 112 113 /* Unlock the garbage collector mutex. */ 114 if (pthread_mutex_unlock(&_gc_mutex) != 0) 115 PANIC("Cannot unlock gc mutex"); 116 117 stack = sizeof(struct stack) 118 + (void *) spare_stack 119 - PTHREAD_STACK_DEFAULT; 120 } else { 121 /* Unlock the garbage collector mutex. */ 122 if (pthread_mutex_unlock(&_gc_mutex) != 0) 123 PANIC("Cannot unlock gc mutex"); 124 125 /* Allocate a new stack. */ 126 stack = _next_stack + PTHREAD_STACK_GUARD; 127 /* 128 * Even if stack allocation fails, we don't want 129 * to try to use this location again, so 130 * unconditionally decrement _next_stack. Under 131 * normal operating conditions, the most likely 132 * reason for an mmap() error is a stack 133 * overflow of the adjacent thread stack. 134 */ 135 _next_stack -= (PTHREAD_STACK_DEFAULT 136 + PTHREAD_STACK_GUARD); 137 138 /* Red zone: */ 139 if (mmap(_next_stack, PTHREAD_STACK_GUARD, 0, 140 MAP_ANON, -1, 0) == MAP_FAILED) { 141 ret = EAGAIN; 142 free(new_thread); 143 } 144 /* Stack: */ 145 else if (mmap(stack, 146 PTHREAD_STACK_DEFAULT, 147 PROT_READ | PROT_WRITE, 148 MAP_STACK, 149 -1, 0) == MAP_FAILED) { 150 ret = EAGAIN; 151 munmap(_next_stack, 152 PTHREAD_STACK_GUARD); 153 free(new_thread); 154 } 155 } 156 } 157 /* 158 * The user wants a stack of a particular size. Lets hope they 159 * really know what they want, and simply malloc the stack. 160 */ 161 else if ((stack = (void *) malloc(pattr->stacksize_attr)) 162 == NULL) { 163 /* Insufficient memory to create a thread: */ 164 ret = EAGAIN; 165 free(new_thread); 166 } 167 168 /* Check for errors: */ 169 if (ret != 0) { 170 } else { 171 /* Initialise the thread structure: */ 172 memset(new_thread, 0, sizeof(struct pthread)); 173 new_thread->slice_usec = -1; 174 new_thread->sig_saved = 0; 175 new_thread->stack = stack; 176 new_thread->start_routine = start_routine; 177 new_thread->arg = arg; 178 179 new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | 180 PTHREAD_CANCEL_DEFERRED; 181 182 /* 183 * Write a magic value to the thread structure 184 * to help identify valid ones: 185 */ 186 new_thread->magic = PTHREAD_MAGIC; 187 188 /* Initialise the thread for signals: */ 189 new_thread->sigmask = _thread_run->sigmask; 190 191 /* Initialise the jump buffer: */ 192 setjmp(new_thread->saved_jmp_buf); 193 194 /* 195 * Set up new stack frame so that it looks like it 196 * returned from a longjmp() to the beginning of 197 * _thread_start(). 198 */ 199#if defined(__FreeBSD__) 200#if defined(__alpha__) 201 new_thread->saved_jmp_buf[0]._jb[2] = (long) _thread_start; 202 new_thread->saved_jmp_buf[0]._jb[4 + R_RA] = 0; 203 new_thread->saved_jmp_buf[0]._jb[4 + R_T12] = (long) _thread_start; 204#else 205 new_thread->saved_jmp_buf[0]._jb[0] = (long) _thread_start; 206#endif 207#elif defined(__NetBSD__) 208#if defined(__alpha__) 209 new_thread->saved_jmp_buf[2] = (long) _thread_start; 210 new_thread->saved_jmp_buf[4 + R_RA] = 0; 211 new_thread->saved_jmp_buf[4 + R_T12] = (long) _thread_start; 212#else 213 new_thread->saved_jmp_buf[0] = (long) _thread_start; 214#endif 215#else 216#error "Don't recognize this operating system!" 217#endif 218 219 /* The stack starts high and builds down: */ 220#if defined(__FreeBSD__) 221#if defined(__alpha__) 222 new_thread->saved_jmp_buf[0]._jb[4 + R_SP] = (long) new_thread->stack + pattr->stacksize_attr - sizeof(double); 223#else 224 new_thread->saved_jmp_buf[0]._jb[2] = (int) (new_thread->stack + pattr->stacksize_attr - sizeof(double)); 225#endif 226#elif defined(__NetBSD__) 227#if defined(__alpha__) 228 new_thread->saved_jmp_buf[4 + R_SP] = (long) new_thread->stack + pattr->stacksize_attr - sizeof(double); 229#else 230 new_thread->saved_jmp_buf[2] = (long) new_thread->stack + pattr->stacksize_attr - sizeof(double); 231#endif 232#else 233#error "Don't recognize this operating system!" 234#endif 235 236 /* Copy the thread attributes: */ 237 memcpy(&new_thread->attr, pattr, sizeof(struct pthread_attr)); 238 239 /* 240 * Check if this thread is to inherit the scheduling 241 * attributes from its parent: 242 */ 243 if (new_thread->attr.flags & PTHREAD_INHERIT_SCHED) { 244 /* Copy the scheduling attributes: */ 245 new_thread->base_priority 246 = _thread_run->base_priority; 247 new_thread->attr.prio 248 = _thread_run->base_priority; 249 new_thread->attr.sched_policy 250 = _thread_run->attr.sched_policy; 251 } else { 252 /* 253 * Use just the thread priority, leaving the 254 * other scheduling attributes as their 255 * default values: 256 */ 257 new_thread->base_priority 258 = new_thread->attr.prio; 259 } 260 new_thread->active_priority = new_thread->base_priority; 261 new_thread->inherited_priority = 0; 262 263 /* Initialise the join queue for the new thread: */ 264 TAILQ_INIT(&(new_thread->join_queue)); 265 266 /* Initialize the mutex queue: */ 267 TAILQ_INIT(&new_thread->mutexq); 268 269 /* Initialise hooks in the thread structure: */ 270 new_thread->specific_data = NULL; 271 new_thread->cleanup = NULL; 272 new_thread->flags = 0; 273 new_thread->poll_data.nfds = 0; 274 new_thread->poll_data.fds = NULL; 275 276 /* 277 * Defer signals to protect the scheduling queues 278 * from access by the signal handler: 279 */ 280 _thread_kern_sig_defer(); 281 282 /* 283 * Initialise the unique id which GDB uses to 284 * track threads. 285 */ 286 new_thread->uniqueid = next_uniqueid++; 287 288 /* 289 * Check if the garbage collector thread 290 * needs to be started. 291 */ 292 f_gc = (TAILQ_FIRST(&_thread_list) == _thread_initial); 293 294 /* Add the thread to the linked list of all threads: */ 295 TAILQ_INSERT_HEAD(&_thread_list, new_thread, tle); 296 297 if (pattr->suspend == PTHREAD_CREATE_SUSPENDED) { 298 new_thread->state = PS_SUSPENDED; 299 PTHREAD_WAITQ_INSERT(new_thread); 300 } else { 301 new_thread->state = PS_RUNNING; 302 PTHREAD_PRIOQ_INSERT_TAIL(new_thread); 303 } 304 305 /* 306 * Undefer and handle pending signals, yielding 307 * if necessary. 308 */ 309 _thread_kern_sig_undefer(); 310 311 /* Return a pointer to the thread structure: */ 312 (*thread) = new_thread; 313 314 /* Schedule the new user thread: */ 315 _thread_kern_sched(NULL); 316 317 /* 318 * Start a garbage collector thread 319 * if necessary. 320 */ 321 if (f_gc && pthread_create(&gc_thread,NULL, 322 _thread_gc,NULL) != 0) 323 PANIC("Can't create gc thread"); 324 } 325 } 326 327 /* Return the status: */ 328 return (ret); 329} 330 331void 332_thread_start(void) 333{ 334 /* We just left the scheduler via longjmp: */ 335 _thread_kern_in_sched = 0; 336 337 /* Run the current thread's start routine with argument: */ 338 pthread_exit(_thread_run->start_routine(_thread_run->arg)); 339 340 /* This point should never be reached. */ 341 PANIC("Thread has resumed after exit"); 342} 343#endif 344