lib/libc_r/uthread/uthread_init.c

   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: src/lib/libc_r/uthread/uthread_init.c,v 1.23.2.11 2003/02/24 23:27:32 das Exp $
  33  */
  34
  35 /* Allocate space for global thread variables here: */
  36 #define GLOBAL_PTHREAD_PRIVATE
  37
  38 #include <sys/user.h>   /* MUST BE FIRST */
  39 #include <errno.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <fcntl.h>
  43 #include <paths.h>
  44 #include <poll.h>
  45 #include <unistd.h>
  46 #include <sys/ioctl.h>
  47 #include <sys/sysctl.h>
  48 #include <sys/time.h>
  49 #include <sys/ttycom.h>
  50 #include <sys/param.h>
  51 #include <sys/mman.h>
  52 #include <machine/reg.h>
  53 #include <pthread.h>
  54 #include "pthread_private.h"
  55
  56 /*
  57  * These are needed when linking statically.  All references within
  58  * libgcc (and in the future libc) to these routines are weak, but
  59  * if they are not (strongly) referenced by the application or other
  60  * libraries, then the actual functions will not be loaded.
  61  */
  62 static void *thread_references[] = {
  63         &_pthread_once,
  64         &_pthread_key_create,
  65         &_pthread_key_delete,
  66         &_pthread_getspecific,
  67         &_pthread_setspecific,
  68         &_pthread_mutex_init,
  69         &_pthread_mutex_destroy,
  70         &_pthread_mutex_lock,
  71         &_pthread_mutex_trylock,
  72         &_pthread_mutex_unlock,
  73         &_pthread_cond_init,
  74         &_pthread_cond_destroy,
  75         &_pthread_cond_wait,
  76         &_pthread_cond_timedwait,
  77         &_pthread_cond_signal,
  78         &_pthread_cond_broadcast
  79 };
  80
  81 #ifdef GCC_2_8_MADE_THREAD_AWARE
  82 typedef void *** (*dynamic_handler_allocator)();
  83 extern void __set_dynamic_handler_allocator(dynamic_handler_allocator);
  84
  85 static pthread_key_t except_head_key;
  86
  87 typedef struct {
  88         void **__dynamic_handler_chain;
  89         void *top_elt[2];
  90 } except_struct;
  91
  92 static void ***dynamic_allocator_handler_fn()
  93 {
  94         except_struct *dh = (except_struct *)pthread_getspecific(except_head_key);
  95
  96         if(dh == NULL) {
  97                 dh = (except_struct *)malloc( sizeof(except_struct) );
  98                 memset(dh, '\0', sizeof(except_struct));
  99                 dh->__dynamic_handler_chain= dh->top_elt;
 100                 pthread_setspecific(except_head_key, (void *)dh);
 101         }
 102         return &dh->__dynamic_handler_chain;
 103 }
 104 #endif /* GCC_2_8_MADE_THREAD_AWARE */
 105
 106 /*
 107  * Threaded process initialization
 108  */
 109
 110 void    _thread_init(void) __attribute__((constructor));
 111
 112 void
 113 _thread_init(void)
 114 {
 115         int             fd;
 116         int             i;
 117         size_t          len;
 118         int             mib[2];
 119         struct clockinfo clockinfo;
 120         struct sigaction act;
 121
 122         /* Check if this function has already been called: */
 123         if (_thread_initial)
 124                 /* Only initialise the threaded application once. */
 125                 return;
 126
 127         /*
 128          * Make gcc quiescent about thread_references not being
 129          * referenced:
 130          */
 131         if (thread_references[0] == NULL)
 132                 PANIC("Mandatory pthread_* functions not loaded");
 133
 134         /*
 135          * Check for the special case of this process running as
 136          * or in place of init as pid = 1:
 137          */
 138         if (getpid() == 1) {
 139                 /*
 140                  * Setup a new session for this process which is
 141                  * assumed to be running as root.
 142                  */
 143                 if (setsid() == -1)
 144                         PANIC("Can't set session ID");
 145                 if (revoke(_PATH_CONSOLE) != 0)
 146                         PANIC("Can't revoke console");
 147                 if ((fd = __sys_open(_PATH_CONSOLE, O_RDWR)) < 0)
 148                         PANIC("Can't open console");
 149                 if (setlogin("root") == -1)
 150                         PANIC("Can't set login to root");
 151                 if (__sys_ioctl(fd, TIOCSCTTY, NULL) == -1)
 152                         PANIC("Can't set controlling terminal");
 153                 if (__sys_dup2(fd, 0) == -1 ||
 154                     __sys_dup2(fd, 1) == -1 ||
 155                     __sys_dup2(fd, 2) == -1)
 156                         PANIC("Can't dup2");
 157         }
 158
 159         /* Get the standard I/O flags before messing with them : */
 160         for (i = 0; i < 3; i++) {
 161                 if (((_pthread_stdio_flags[i] =
 162                     __sys_fcntl(i, F_GETFL, NULL)) == -1) &&
 163                     (errno != EBADF))
 164                         PANIC("Cannot get stdio flags");
 165         }
 166
 167         /*
 168          * Create a pipe that is written to by the signal handler to prevent
 169          * signals being missed in calls to _select:
 170          */
 171         _thread_mksigpipe();
 172
 173         /* Allocate and initialize the ready queue: */
 174         if (_pq_alloc(&_readyq, PTHREAD_MIN_PRIORITY, PTHREAD_LAST_PRIORITY) != 0) {
 175                 /* Abort this application: */
 176                 PANIC("Cannot allocate priority ready queue.");
 177         }
 178         /* Allocate memory for the thread structure of the initial thread: */
 179         else if ((_thread_initial = (pthread_t) malloc(sizeof(struct pthread))) == NULL) {
 180                 /*
 181                  * Insufficient memory to initialise this application, so
 182                  * abort:
 183                  */
 184                 PANIC("Cannot allocate memory for initial thread");
 185         }
 186         /* Allocate memory for the scheduler stack: */
 187         else if ((_thread_kern_sched_stack = malloc(SCHED_STACK_SIZE)) == NULL)
 188                 PANIC("Failed to allocate stack for scheduler");
 189         else {
 190                 /* Zero the global kernel thread structure: */
 191                 memset(&_thread_kern_thread, 0, sizeof(struct pthread));
 192                 _thread_kern_thread.flags = PTHREAD_FLAGS_PRIVATE;
 193                 _thread_kern_thread.tcb = _libc_allocate_tls();
 194                 memset(_thread_initial, 0, sizeof(struct pthread));
 195
 196                 /* Initialize the waiting and work queues: */
 197                 TAILQ_INIT(&_waitingq);
 198                 TAILQ_INIT(&_workq);
 199
 200                 /* Initialize the scheduling switch hook routine: */
 201                 _sched_switch_hook = NULL;
 202
 203                 /* Give this thread default attributes: */
 204                 memcpy((void *) &_thread_initial->attr, &pthread_attr_default,
 205                     sizeof(struct pthread_attr));
 206
 207                 /* Initialize the thread stack cache: */
 208                 SLIST_INIT(&_stackq);
 209
 210                 /* Find the stack top */
 211                 mib[0] = CTL_KERN;
 212                 mib[1] = KERN_USRSTACK;
 213                 len = sizeof (int);
 214                 if (sysctl(mib, 2, &_usrstack, &len, NULL, 0) == -1)
 215                         _usrstack = (void *)USRSTACK;
 216                 _next_stack = _usrstack - PTHREAD_STACK_INITIAL -
 217                     PTHREAD_STACK_DEFAULT - (2 * PTHREAD_STACK_GUARD);
 218                 /*
 219                  * Create a red zone below the main stack.  All other stacks are
 220                  * constrained to a maximum size by the paramters passed to
 221                  * mmap(), but this stack is only limited by resource limits, so
 222                  * this stack needs an explicitly mapped red zone to protect the
 223                  * thread stack that is just beyond.
 224                  */
 225                 if (mmap(_usrstack - PTHREAD_STACK_INITIAL -
 226                     PTHREAD_STACK_GUARD, PTHREAD_STACK_GUARD, 0,
 227                     MAP_ANON | MAP_TRYFIXED, -1, 0) == MAP_FAILED)
 228                         PANIC("Cannot allocate red zone for initial thread");
 229
 230                 _thread_initial->tcb = tls_get_tcb();
 231                 /* Set the main thread stack pointer. */
 232                 _thread_initial->stack = _usrstack - PTHREAD_STACK_INITIAL;
 233
 234                 /* Set the stack attributes: */
 235                 _thread_initial->attr.stackaddr_attr = _thread_initial->stack;
 236                 _thread_initial->attr.stacksize_attr = PTHREAD_STACK_INITIAL;
 237
 238                 /* Setup the context for the scheduler: */
 239                 _setjmp(_thread_kern_sched_jb);
 240                 SET_STACK_JB(_thread_kern_sched_jb, _thread_kern_sched_stack +
 241                     SCHED_STACK_SIZE - sizeof(double));
 242                 SET_RETURN_ADDR_JB(_thread_kern_sched_jb, _thread_kern_scheduler);
 243
 244                 /*
 245                  * Write a magic value to the thread structure
 246                  * to help identify valid ones:
 247                  */
 248                 _thread_initial->magic = PTHREAD_MAGIC;
 249
 250                 /* Set the initial cancel state */
 251                 _thread_initial->cancelflags = PTHREAD_CANCEL_ENABLE |
 252                     PTHREAD_CANCEL_DEFERRED;
 253
 254                 /* Default the priority of the initial thread: */
 255                 _thread_initial->base_priority = PTHREAD_DEFAULT_PRIORITY;
 256                 _thread_initial->active_priority = PTHREAD_DEFAULT_PRIORITY;
 257                 _thread_initial->inherited_priority = 0;
 258
 259                 /* Initialise the state of the initial thread: */
 260                 _thread_initial->state = PS_RUNNING;
 261
 262                 /* Set the name of the thread: */
 263                 _thread_initial->name = strdup("_thread_initial");
 264
 265                 /* Initialize joiner to NULL (no joiner): */
 266                 _thread_initial->joiner = NULL;
 267
 268                 /* Initialize the owned mutex queue and count: */
 269                 TAILQ_INIT(&(_thread_initial->mutexq));
 270                 _thread_initial->priority_mutex_count = 0;
 271
 272                 /* Initialize the global scheduling time: */
 273                 _sched_ticks = 0;
 274                 gettimeofday((struct timeval *) &_sched_tod, NULL);
 275
 276                 /* Initialize last active: */
 277                 _thread_initial->last_active = (long) _sched_ticks;
 278
 279                 /* Initialize the initial context: */
 280                 _thread_initial->curframe = NULL;
 281
 282                 /* Initialise the rest of the fields: */
 283                 _thread_initial->poll_data.nfds = 0;
 284                 _thread_initial->poll_data.fds = NULL;
 285                 _thread_initial->sig_defer_count = 0;
 286                 _thread_initial->yield_on_sig_undefer = 0;
 287                 _thread_initial->specific_data = NULL;
 288                 _thread_initial->cleanup = NULL;
 289                 _thread_initial->flags = 0;
 290                 TAILQ_INIT(&_thread_list);
 291                 TAILQ_INSERT_HEAD(&_thread_list, _thread_initial, tle);
 292                 _set_curthread(_thread_initial);
 293                 TAILQ_INIT(&_atfork_list);
 294                 _pthread_mutex_init(&_atfork_mutex, NULL);
 295
 296                 /* Initialise the global signal action structure: */
 297                 sigfillset(&act.sa_mask);
 298                 act.sa_handler = (void (*) ()) _thread_sig_handler;
 299                 act.sa_flags = SA_SIGINFO | SA_RESTART;
 300
 301                 /* Clear pending signals for the process: */
 302                 sigemptyset(&_process_sigpending);
 303
 304                 /* Clear the signal queue: */
 305                 memset(_thread_sigq, 0, sizeof(_thread_sigq));
 306
 307                 /* Enter a loop to get the existing signal status: */
 308                 for (i = 1; i < NSIG; i++) {
 309                         /* Check for signals which cannot be trapped: */
 310                         if (i == SIGKILL || i == SIGSTOP) {
 311                         }
 312
 313                         /* Get the signal handler details: */
 314                         else if (__sys_sigaction(i, NULL,
 315                             &_thread_sigact[i - 1]) != 0) {
 316                                 /*
 317                                  * Abort this process if signal
 318                                  * initialisation fails:
 319                                  */
 320                                 PANIC("Cannot read signal handler info");
 321                         }
 322
 323                         /* Initialize the SIG_DFL dummy handler count. */
 324                         _thread_dfl_count[i] = 0;
 325                 }
 326
 327                 /*
 328                  * Install the signal handler for the most important
 329                  * signals that the user-thread kernel needs. Actually
 330                  * SIGINFO isn't really needed, but it is nice to have.
 331                  */
 332                 if (__sys_sigaction(_SCHED_SIGNAL, &act, NULL) != 0 ||
 333                     __sys_sigaction(SIGINFO,       &act, NULL) != 0 ||
 334                     __sys_sigaction(SIGCHLD,       &act, NULL) != 0) {
 335                         /*
 336                          * Abort this process if signal initialisation fails:
 337                          */
 338                         PANIC("Cannot initialise signal handler");
 339                 }
 340                 _thread_sigact[_SCHED_SIGNAL - 1].sa_flags = SA_SIGINFO;
 341                 _thread_sigact[SIGINFO - 1].sa_flags = SA_SIGINFO;
 342                 _thread_sigact[SIGCHLD - 1].sa_flags = SA_SIGINFO;
 343
 344                 /* Get the process signal mask: */
 345                 __sys_sigprocmask(SIG_SETMASK, NULL, &_process_sigmask);
 346
 347                 /* Get the kernel clockrate: */
 348                 mib[0] = CTL_KERN;
 349                 mib[1] = KERN_CLOCKRATE;
 350                 len = sizeof (struct clockinfo);
 351                 if (sysctl(mib, 2, &clockinfo, &len, NULL, 0) == 0)
 352                         _clock_res_usec = clockinfo.tick > CLOCK_RES_USEC_MIN ?
 353                             clockinfo.tick : CLOCK_RES_USEC_MIN;
 354
 355                 /* Get the table size: */
 356                 if ((_thread_dtablesize = getdtablesize()) < 0) {
 357                         /*
 358                          * Cannot get the system defined table size, so abort
 359                          * this process.
 360                          */
 361                         PANIC("Cannot get dtablesize");
 362                 }
 363                 /* Allocate memory for the file descriptor table: */
 364                 if ((_thread_fd_table = (struct fd_table_entry **) malloc(sizeof(struct fd_table_entry *) * _thread_dtablesize)) == NULL) {
 365                         /* Avoid accesses to file descriptor table on exit: */
 366                         _thread_dtablesize = 0;
 367
 368                         /*
 369                          * Cannot allocate memory for the file descriptor
 370                          * table, so abort this process.
 371                          */
 372                         PANIC("Cannot allocate memory for file descriptor table");
 373                 }
 374                 /* Allocate memory for the pollfd table: */
 375                 if ((_thread_pfd_table = (struct pollfd *) malloc(sizeof(struct pollfd) * _thread_dtablesize)) == NULL) {
 376                         /*
 377                          * Cannot allocate memory for the file descriptor
 378                          * table, so abort this process.
 379                          */
 380                         PANIC("Cannot allocate memory for pollfd table");
 381                 } else {
 382                         /*
 383                          * Enter a loop to initialise the file descriptor
 384                          * table:
 385                          */
 386                         for (i = 0; i < _thread_dtablesize; i++) {
 387                                 /* Initialise the file descriptor table: */
 388                                 _thread_fd_table[i] = NULL;
 389                         }
 390
 391                         /* Initialize stdio file descriptor table entries: */
 392                         for (i = 0; i < 3; i++) {
 393                                 if ((_thread_fd_table_init(i) != 0) &&
 394                                     (errno != EBADF))
 395                                         PANIC("Cannot initialize stdio file "
 396                                             "descriptor table entry");
 397                         }
 398                 }
 399         }
 400
 401 #ifdef GCC_2_8_MADE_THREAD_AWARE
 402         /* Create the thread-specific data for the exception linked list. */
 403         if(pthread_key_create(&except_head_key, NULL) != 0)
 404                 PANIC("Failed to create thread specific execption head");
 405
 406         /* Setup the gcc exception handler per thread. */
 407         __set_dynamic_handler_allocator( dynamic_allocator_handler_fn );
 408 #endif /* GCC_2_8_MADE_THREAD_AWARE */
 409
 410         /* Initialise the garbage collector mutex and condition variable. */
 411         if (pthread_mutex_init(&_gc_mutex,NULL) != 0 ||
 412             pthread_cond_init(&_gc_cond,NULL) != 0)
 413                 PANIC("Failed to initialise garbage collector mutex or condvar");
 414 }
 415
 416 int _thread_autoinit_dummy_decl = 0;
 417
 418
 419 void
 420 _thread_mksigpipe(void)
 421 {
 422         int fd, flags, i;
 423
 424         /*
 425          * Create a pipe that is written to by the signal handler to
 426          * prevent signals being missed in calls to
 427          * __sys_select:
 428          */
 429         if (__sys_pipe(_thread_kern_pipe) != 0) {
 430                 /* Cannot create pipe, so abort: */
 431                 PANIC("Cannot create pthread kernel pipe.");
 432         }
 433         /*
 434          * Make sure the pipe does not get in the way of stdio:
 435          */
 436         for (i = 0; i < 2; i++) {
 437                 if (_thread_kern_pipe[i] < 3) {
 438                         fd = __sys_fcntl(_thread_kern_pipe[i], F_DUPFD, 3);
 439                         if (fd == -1)
 440                             PANIC("Cannot create kernel pipe");
 441                         __sys_close(_thread_kern_pipe[i]);
 442                         _thread_kern_pipe[i] = fd;
 443                 }
 444         }
 445         /* Get the flags for the read pipe: */
 446         if ((flags = __sys_fcntl(_thread_kern_pipe[0], F_GETFL, NULL)) == -1)
 447                 abort();
 448         /* Make the read pipe non-blocking: */
 449         if (__sys_fcntl(_thread_kern_pipe[0], F_SETFL, flags | O_NONBLOCK) == -1)
 450                 abort();
 451         /* Get the flags for the write pipe: */
 452         if ((flags = __sys_fcntl(_thread_kern_pipe[1], F_GETFL, NULL)) == -1)
 453                 abort();
 454         /* Make the write pipe non-blocking: */
 455         if (__sys_fcntl(_thread_kern_pipe[1], F_SETFL, flags | O_NONBLOCK) == -1)
 456                 abort();
 457 }