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     .ptr___pthread_unwind = &__pthread_unwind
 126   };
 127 # define ptr_pthread_functions &pthread_functions
 128 #else
 129 # define ptr_pthread_functions NULL
 130 #endif
 131
 132
 133 /* For asynchronous cancellation we use a signal.  This is the handler.  */
 134 static void
 135 sigcancel_handler (int sig __attribute ((unused)))
 136 {
 137   struct pthread *self = THREAD_SELF;
 138
 139   int oldval = THREAD_GETMEM (self, cancelhandling);
 140   while (1)
 141     {
 142       /* We are canceled now.  When canceled by another thread this flag
 143          is already set but if the signal is directly send (internally or
 144          from another process) is has to be done here.  */
 145       int newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK;
 146
 147       if (oldval == newval || (oldval & EXITING_BITMASK) != 0)
 148         /* Already canceled or exiting.  */
 149         break;
 150
 151       int curval = THREAD_ATOMIC_CMPXCHG_VAL (self, cancelhandling, newval,
 152                                               oldval);
 153       if (curval == oldval)
 154         {
 155           /* Set the return value.  */
 156           THREAD_SETMEM (self, result, PTHREAD_CANCELED);
 157
 158           /* Make sure asynchronous cancellation is still enabled.  */
 159           if ((newval & CANCELTYPE_BITMASK) != 0)
 160             /* Run the registered destructors and terminate the thread.  */
 161             __do_cancel ();
 162
 163           break;
 164         }
 165
 166       oldval = curval;
 167     }
 168 }
 169
 170
 171 /* When using __thread for this, we do it in libc so as not
 172    to give libpthread its own TLS segment just for this.  */
 173 extern void **__libc_dl_error_tsd (void) __attribute__ ((const));
 174
 175
 176 void
 177 __pthread_initialize_minimal_internal (void)
 178 {
 179 #ifndef SHARED
 180   /* Unlike in the dynamically linked case the dynamic linker has not
 181      taken care of initializing the TLS data structures.  */
 182   __libc_setup_tls (TLS_TCB_SIZE, TLS_TCB_ALIGN);
 183
 184   /* We must prevent gcc from being clever and move any of the
 185      following code ahead of the __libc_setup_tls call.  This function
 186      will initialize the thread register which is subsequently
 187      used.  */
 188   __asm __volatile ("");
 189 #endif
 190
 191   /* Minimal initialization of the thread descriptor.  */
 192   struct pthread *pd = THREAD_SELF;
 193   INTERNAL_SYSCALL_DECL (err);
 194   pd->tid = INTERNAL_SYSCALL (set_tid_address, err, 1, &pd->tid);
 195   THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]);
 196   THREAD_SETMEM (pd, user_stack, true);
 197   if (LLL_LOCK_INITIALIZER != 0)
 198     THREAD_SETMEM (pd, lock, LLL_LOCK_INITIALIZER);
 199 #if HP_TIMING_AVAIL
 200   THREAD_SETMEM (pd, cpuclock_offset, GL(dl_cpuclock_offset));
 201 #endif
 202
 203   /* Initialize the list of all running threads with the main thread.  */
 204   INIT_LIST_HEAD (&__stack_user);
 205   list_add (&pd->list, &__stack_user);
 206
 207
 208   /* Install the cancellation signal handler.  If for some reason we
 209      cannot install the handler we do not abort.  Maybe we should, but
 210      it is only asynchronous cancellation which is affected.  */
 211   struct sigaction sa;
 212   sa.sa_handler = sigcancel_handler;
 213   sa.sa_flags = 0;
 214   sigemptyset (&sa.sa_mask);
 215
 216   (void) __libc_sigaction (SIGCANCEL, &sa, NULL);
 217
 218   /* The parent process might have left the signal blocked.  Just in
 219      case, unblock it.  We reuse the signal mask in the sigaction
 220      structure.  It is already cleared.  */
 221   __sigaddset (&sa.sa_mask, SIGCANCEL);
 222   (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &sa.sa_mask,
 223                            NULL, _NSIG / 8);
 224
 225
 226   /* Determine the default allowed stack size.  This is the size used
 227      in case the user does not specify one.  */
 228   struct rlimit limit;
 229   if (getrlimit (RLIMIT_STACK, &limit) != 0
 230       || limit.rlim_cur == RLIM_INFINITY)
 231     /* The system limit is not usable.  Use an architecture-specific
 232        default.  */
 233     limit.rlim_cur = ARCH_STACK_DEFAULT_SIZE;
 234
 235 #ifdef NEED_SEPARATE_REGISTER_STACK
 236   __default_stacksize = MAX (limit.rlim_cur / 2, PTHREAD_STACK_MIN);
 237 #else
 238   __default_stacksize = MAX (limit.rlim_cur, PTHREAD_STACK_MIN);
 239 #endif
 240   /* The maximum page size better should be a multiple of the page
 241      size.  */
 242   assert (__default_stacksize % __sysconf (_SC_PAGESIZE) == 0);
 243
 244   /* Get the size of the static and alignment requirements for the TLS
 245      block.  */
 246   size_t static_tls_align;
 247   _dl_get_tls_static_info (&__static_tls_size, &static_tls_align);
 248
 249   /* Make sure the size takes all the alignments into account.  */
 250   if (STACK_ALIGN > static_tls_align)
 251     static_tls_align = STACK_ALIGN;
 252   __static_tls_align_m1 = static_tls_align - 1;
 253
 254   __static_tls_size = roundup (__static_tls_size, static_tls_align);
 255
 256 #ifdef SHARED
 257   /* Transfer the old value from the dynamic linker's internal location.  */
 258   *__libc_dl_error_tsd () = *(*GL(dl_error_catch_tsd)) ();
 259   GL(dl_error_catch_tsd) = &__libc_dl_error_tsd;
 260 #endif
 261
 262   /* Register the fork generation counter with the libc.  */
 263 #ifndef TLS_MULTIPLE_THREADS_IN_TCB
 264   __libc_multiple_threads_ptr =
 265 #endif
 266     __libc_pthread_init (&__fork_generation, __reclaim_stacks,
 267                          ptr_pthread_functions);
 268 }
 269 strong_alias (__pthread_initialize_minimal_internal,
 270               __pthread_initialize_minimal)