nptl/sysdeps/s390/pthread_spin_trylock.c

   1 /* Copyright (C) 2003-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
   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, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include "pthreadP.h"
  21
  22 int
  23 pthread_spin_trylock (lock)
  24      pthread_spinlock_t *lock;
  25 {
  26   int old;
  27
  28   __asm __volatile ("cs %0,%3,%1"
  29                     : "=d" (old), "=Q" (*lock)
  30                     : "0" (0), "d" (1), "m" (*lock) : "cc" );
  31
  32   return old != 0 ? EBUSY : 0;
  33 }