glibc/sysdeps/s390/nptl/pthread_spin_lock.c

33 lines
1.1 KiB
C

/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Martin Schwidefsky <schwidefsky@de.ibm.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 oldval;
__asm__ __volatile__ ("0: lhi %0,0\n"
" cs %0,%2,%1\n"
" jl 0b"
: "=&d" (oldval), "=Q" (*lock)
: "d" (1), "m" (*lock) : "cc" );
return 0;
}