nptl/init.c

   1 /* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <assert.h>
  21 #include <limits.h>
  22 #include <signal.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25 #include <sys/param.h>
  26 #include <sys/resource.h>
  27 #include <pthreadP.h>
  28 #include <atomic.h>
  29 #include <ldsodefs.h>
  30 #include <tls.h>
  31 #include <fork.h>
  32 #include <version.h>
  33 #include <shlib-compat.h>
  34
  35
  36 #ifndef __NR_set_tid_address
  37 /* XXX For the time being...  Once we can rely on the kernel headers
  38    having the definition remove these lines.  */
  39 #if defined __s390__
  40 # define __NR_set_tid_address   252
  41 #elif defined __ia64__
  42 # define __NR_set_tid_address   1233
  43 #elif defined __i386__
  44 # define __NR_set_tid_address   258
  45 #elif defined __x86_64__
  46 # define __NR_set_tid_address   218
  47 #elif defined __powerpc__
  48 # define __NR_set_tid_address   232
  49 #else
  50 # error "define __NR_set_tid_address"
  51 #endif
  52 #endif
  53
  54
  55 /* Default stack size.  */
  56 size_t __default_stacksize attribute_hidden;
  57
  58 /* Size and alignment of static TLS block.  */
  59 size_t __static_tls_size;
  60 size_t __static_tls_align_m1;
  61
  62 /* Version of the library, used in libthread_db to detect mismatches.  */
  63 static const char nptl_version[] = VERSION;
  64
  65
  66 #if defined USE_TLS && !defined SHARED
  67 extern void __libc_setup_tls (size_t tcbsize, size_t tcbalign);
  68 #endif
  69
  70
  71 #ifdef SHARED
  72 static struct pthread_functions pthread_functions =
  73   {
  74     .ptr_pthread_attr_destroy = __pthread_attr_destroy,
  75 # if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)
  76     .ptr___pthread_attr_init_2_0 = __pthread_attr_init_2_0,
  77 # endif
  78     .ptr___pthread_attr_init_2_1 = __pthread_attr_init_2_1,
  79     .ptr_pthread_attr_getdetachstate = __pthread_attr_getdetachstate,
  80     .ptr_pthread_attr_setdetachstate = __pthread_attr_setdetachstate,
  81     .ptr_pthread_attr_getinheritsched = __pthread_attr_getinheritsched,
  82     .ptr_pthread_attr_setinheritsched = __pthread_attr_setinheritsched,
  83     .ptr_pthread_attr_getschedparam = __pthread_attr_getschedparam,
  84     .ptr_pthread_attr_setschedparam = __pthread_attr_setschedparam,
  85     .ptr_pthread_attr_getschedpolicy = __pthread_attr_getschedpolicy,
  86     .ptr_pthread_attr_setschedpolicy = __pthread_attr_setschedpolicy,
  87     .ptr_pthread_attr_getscope = __pthread_attr_getscope,
  88     .ptr_pthread_attr_setscope = __pthread_attr_setscope,
  89     .ptr_pthread_condattr_destroy = __pthread_condattr_destroy,
  90     .ptr_pthread_condattr_init = __pthread_condattr_init,
  91     .ptr___pthread_cond_broadcast = __pthread_cond_broadcast,
  92     .ptr___pthread_cond_destroy = __pthread_cond_destroy,
  93     .ptr___pthread_cond_init = __pthread_cond_init,
  94     .ptr___pthread_cond_signal = __pthread_cond_signal,
  95     .ptr___pthread_cond_wait = __pthread_cond_wait,
  96 # if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_3_2)
  97     .ptr___pthread_cond_broadcast_2_0 = __pthread_cond_broadcast_2_0,
  98     .ptr___pthread_cond_destroy_2_0 = __pthread_cond_destroy_2_0,
  99     .ptr___pthread_cond_init_2_0 = __pthread_cond_init_2_0,
 100     .ptr___pthread_cond_signal_2_0 = __pthread_cond_signal_2_0,
 101     .ptr___pthread_cond_wait_2_0 = __pthread_cond_wait_2_0,
 102 # endif
 103     .ptr_pthread_equal = __pthread_equal,
 104     .ptr___pthread_exit = __pthread_exit,
 105     .ptr_pthread_getschedparam = __pthread_getschedparam,
 106     .ptr_pthread_setschedparam = __pthread_setschedparam,
 107     .ptr_pthread_mutex_destroy = INTUSE(__pthread_mutex_destroy),
 108     .ptr_pthread_mutex_init = INTUSE(__pthread_mutex_init),
 109     .ptr_pthread_mutex_lock = INTUSE(__pthread_mutex_lock),
 110     .ptr_pthread_mutex_unlock = INTUSE(__pthread_mutex_unlock),
 111     .ptr_pthread_self = __pthread_self,
 112     .ptr_pthread_setcancelstate = __pthread_setcancelstate,
 113     .ptr_pthread_setcanceltype = __pthread_setcanceltype,
 114     .ptr___pthread_cleanup_upto = __pthread_cleanup_upto,
 115     .ptr___pthread_once = __pthread_once_internal,
 116     .ptr___pthread_rwlock_rdlock = __pthread_rwlock_rdlock_internal,
 117     .ptr___pthread_rwlock_wrlock = __pthread_rwlock_wrlock_internal,
 118     .ptr___pthread_rwlock_unlock = __pthread_rwlock_unlock_internal,
 119     .ptr___pthread_key_create = __pthread_key_create_internal,
 120     .ptr___pthread_getspecific = __pthread_getspecific_internal,
 121     .ptr___pthread_setspecific = __pthread_setspecific_internal,
 122     .ptr__pthread_cleanup_push_defer = __pthread_cleanup_push_defer,
 123     .ptr__pthread_cleanup_pop_restore = __pthread_cleanup_pop_restore,
 124     .ptr_nthreads = &__nptl_nthreads
 125   };
 126 # define ptr_pthread_functions &pthread_functions
 127 #else
 128 # define ptr_pthread_functions NULL
 129 #endif
 130
 131
 132 /* For asynchronous cancellation we use a signal.  This is the handler.  */
 133 static void
 134 sigcancel_handler (int sig __attribute ((unused)))
 135 {
 136   struct pthread *self = THREAD_SELF;
 137
 138   while (1)
 139     {
 140       /* We are canceled now.  When canceled by another thread this flag
 141          is already set but if the signal is directly send (internally or
 142          from another process) is has to be done here.  */
 143       int oldval = THREAD_GETMEM (self, cancelhandling);
 144       int newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK;
 145
 146       if (oldval == newval || (oldval & EXITING_BITMASK) != 0)
 147         /* Already canceled or exiting.  */
 148         break;
 149
 150       if (atomic_compare_and_exchange_acq (&self->cancelhandling, newval,
 151                                            oldval) == 0)
 152         {
 153           /* Set the return value.  */
 154           THREAD_SETMEM (self, result, PTHREAD_CANCELED);
 155
 156           /* Make sure asynchronous cancellation is still enabled.  */
 157           if ((newval & CANCELTYPE_BITMASK) != 0)
 158             {
 159               /* The thread is exiting now.  */
 160               atomic_bit_set (&self->cancelhandling, EXITING_BIT);
 161
 162               /* Run the registered destructors and terminate the
 163                  thread.  */
 164               __do_cancel ();
 165             }
 166
 167           break;
 168         }
 169     }
 170 }
 171
 172
 173 /* When using __thread for this, we do it in libc so as not
 174    to give libpthread its own TLS segment just for this.  */
 175 extern void **__libc_dl_error_tsd (void) __attribute__ ((const));
 176
 177
 178 void
 179 __pthread_initialize_minimal_internal (void)
 180 {
 181 #ifndef SHARED
 182   /* Unlike in the dynamically linked case the dynamic linker has not
 183      taken care of initializing the TLS data structures.  */
 184   __libc_setup_tls (TLS_TCB_SIZE, TLS_TCB_ALIGN);
 185
 186   /* We must prevent gcc from being clever and move any of the
 187      following code ahead of the __libc_setup_tls call.  This function
 188      will initialize the thread register which is subsequently
 189      used.  */
 190   __asm __volatile ("");
 191 #endif
 192
 193   /* Minimal initialization of the thread descriptor.  */
 194   struct pthread *pd = THREAD_SELF;
 195   INTERNAL_SYSCALL_DECL (err);
 196   pd->tid = INTERNAL_SYSCALL (set_tid_address, err, 1, &pd->tid);
 197   THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]);
 198   THREAD_SETMEM (pd, user_stack, true);
 199   if (LLL_LOCK_INITIALIZER != 0)
 200     THREAD_SETMEM (pd, lock, LLL_LOCK_INITIALIZER);
 201 #if HP_TIMING_AVAIL
 202   THREAD_SETMEM (pd, cpuclock_offset, GL(dl_cpuclock_offset));
 203 #endif
 204
 205   /* Initialize the list of all running threads with the main thread.  */
 206   INIT_LIST_HEAD (&__stack_user);
 207   list_add (&pd->list, &__stack_user);
 208
 209
 210   /* Install the cancellation signal handler.  If for some reason we
 211      cannot install the handler we do not abort.  Maybe we should, but
 212      it is only asynchronous cancellation which is affected.  */
 213   struct sigaction sa;
 214   sa.sa_handler = sigcancel_handler;
 215   sa.sa_flags = 0;
 216   sigemptyset (&sa.sa_mask);
 217
 218   (void) __libc_sigaction (SIGCANCEL, &sa, NULL);
 219
 220   /* The parent process might have left the signal blocked.  Just in
 221      case, unblock it.  We reuse the signal mask in the sigaction
 222      structure.  It is already cleared.  */
 223   __sigaddset (&sa.sa_mask, SIGCANCEL);
 224   (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &sa.sa_mask,
 225                            NULL, _NSIG / 8);
 226
 227
 228   /* Determine the default allowed stack size.  This is the size used
 229      in case the user does not specify one.  */
 230   struct rlimit limit;
 231   if (getrlimit (RLIMIT_STACK, &limit) != 0
 232       || limit.rlim_cur == RLIM_INFINITY)
 233     /* The system limit is not usable.  Use an architecture-specific
 234        default.  */
 235     limit.rlim_cur = ARCH_STACK_DEFAULT_SIZE;
 236
 237 #ifdef NEED_SEPARATE_REGISTER_STACK
 238   __default_stacksize = MAX (limit.rlim_cur / 2, PTHREAD_STACK_MIN);
 239 #else
 240   __default_stacksize = MAX (limit.rlim_cur, PTHREAD_STACK_MIN);
 241 #endif
 242   /* The maximum page size better should be a multiple of the page
 243      size.  */
 244   assert (__default_stacksize % __sysconf (_SC_PAGESIZE) == 0);
 245
 246   /* Get the size of the static and alignment requirements for the TLS
 247      block.  */
 248   size_t static_tls_align;
 249   _dl_get_tls_static_info (&__static_tls_size, &static_tls_align);
 250
 251   /* Make sure the size takes all the alignments into account.  */
 252   if (STACK_ALIGN > static_tls_align)
 253     static_tls_align = STACK_ALIGN;
 254   __static_tls_align_m1 = static_tls_align - 1;
 255
 256   __static_tls_size = roundup (__static_tls_size, static_tls_align);
 257
 258 #ifdef SHARED
 259   /* Transfer the old value from the dynamic linker's internal location.  */
 260   *__libc_dl_error_tsd () = *(*GL(dl_error_catch_tsd)) ();
 261   GL(dl_error_catch_tsd) = &__libc_dl_error_tsd;
 262 #endif
 263
 264   /* Register the fork generation counter with the libc.  */
 265 #ifndef TLS_MULTIPLE_THREADS_IN_TCB
 266   __libc_multiple_threads_ptr =
 267 #endif
 268     __libc_pthread_init (&__fork_generation, __reclaim_stacks,
 269                          ptr_pthread_functions);
 270 }
 271 strong_alias (__pthread_initialize_minimal_internal,
 272               __pthread_initialize_minimal)