pthread_spin_trylock.c 1.2 KB

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  1. /* Copyright (C) 2003 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
  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, write to the Free
  14. Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  15. 02111-1307 USA. */
  16. #include <errno.h>
  17. #include "pthreadP.h"
  18. int
  19. pthread_spin_trylock (pthread_spinlock_t *lock)
  20. {
  21. int res;
  22. __asm__ __volatile
  23. ("ldstub [%1], %0\n"
  24. "membar #StoreLoad | #StoreStore"
  25. : "=r" (res)
  26. : "r" (lock)
  27. : "memory");
  28. return res == 0 ? 0 : EBUSY;
  29. }