nptl/sysdeps/sparc/sparc32/sparcv9/pthread_spin_lock.c

   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
   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 "pthreadP.h"
  21
  22 int
  23 pthread_spin_lock (pthread_spinlock_t *lock)
  24 {
  25   __asm __volatile
  26     ("1: ldstub  [%0], %%g2\n"
  27      "   brnz,pn %%g2, 2f\n"
  28      "    membar #StoreLoad | #StoreStore\n"
  29      ".subsection 2\n"
  30      "2: ldub    [%0], %%g2\n"
  31      "   brnz,pt %%g2, 2b\n"
  32      "    membar #LoadLoad\n"
  33      "   b,a,pt  %%xcc, 1b\n"
  34      ".previous"
  35      : /* no outputs */
  36      : "r" (lock)
  37      : "g2", "memory");
  38   return 0;
  39 }