createthread.c 2.1 KB

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  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. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. /* The "thread register" gets initialized from a segment descriptor.
  16. Initialize such a descriptor first. */
  17. #define PREPARE_CREATE \
  18. union user_desc_init desc; \
  19. \
  20. /* Describe the thread-local storage segment. */ \
  21. \
  22. /* The 'entry_number' field. The first three bits of the segment \
  23. register value select the GDT, ignore them. We get the index \
  24. from the value of the %gs register in the current thread. */ \
  25. desc.vals[0] = TLS_GET_GS () >> 3; \
  26. /* The 'base_addr' field. Pointer to the TCB. */ \
  27. desc.vals[1] = (unsigned long int) pd; \
  28. /* The 'limit' field. We use 4GB which is 0xfffff pages. */ \
  29. desc.vals[2] = 0xfffff; \
  30. /* Collapsed value of the bitfield: \
  31. .seg_32bit = 1 \
  32. .contents = 0 \
  33. .read_exec_only = 0 \
  34. .limit_in_pages = 1 \
  35. .seg_not_present = 0 \
  36. .useable = 1 */ \
  37. desc.vals[3] = 0x51
  38. /* Value passed to 'clone' for initialization of the thread register. */
  39. #define TLS_VALUE &desc.desc
  40. /* Get the real implementation. */
  41. #include <sysdeps/pthread/createthread.c>