/* Copyright (C) 2003-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include "pthreadP.h"

int

pthread_spin_lock (pthread_spinlock_t *lock)

{

  int *p = (int *) lock;

  while (__builtin_expect (__sync_val_compare_and_swap (p, 0, 1), 0))

    {

      /* Spin without using the atomic instruction.  */

      do

	__asm __volatile ("hint @pause" : : : "memory");

      while (*p);

    }

  return 0;

}