nptl/sysdeps/s390/pthread_spin_trylock.c

   1 /* Copyright (C) 2003 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include "pthreadP.h"
  22
  23 int
  24 pthread_spin_trylock (lock)
  25      pthread_spinlock_t *lock;
  26 {
  27   int old;
  28
  29   __asm __volatile ("cs %0,%3,%1"
  30                     : "=d" (old), "=Q" (*lock)
  31                     : "0" (0), "d" (1), "m" (*lock) : "cc" );
  32
  33   return old != 0 ? EBUSY : 0;
  34 }