summary refs log tree commit diff
path: root/sysdeps/mach/hppa/machine-lock.h
blob: 0a178357a3549d87d8b1f73d4d3462df64661f5a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
/* Machine-specific definition for spin locks.  HPPA version.
Copyright (C) 1995 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#ifndef _MACHINE_LOCK_H
#define	_MACHINE_LOCK_H

/* The type of a spin lock variable.  */

typedef __volatile int __spin_lock_t __attribute__ ((__aligned__ (16)));

/* Value to initialize `__spin_lock_t' variables to.  */

#define	__SPIN_LOCK_INITIALIZER	-1


#ifndef _EXTERN_INLINE
#define _EXTERN_INLINE extern __inline
#endif

/* Unlock LOCK.  */

_EXTERN_INLINE void
__spin_unlock (__spin_lock_t *__lock)
{
  *__lock = -1;
}

/* Try to lock LOCK; return nonzero if we locked it, zero if another has.  */

_EXTERN_INLINE int
__spin_try_lock (__spin_lock_t *__lock)
{
  register int __result;
  __asm__ __volatile__ ("ldcws %0, %1" : "=m" (*__lock), "=r" (__result));
  return __result != 0;
}

/* Return nonzero if LOCK is locked.  */

_EXTERN_INLINE int
__spin_lock_locked (__spin_lock_t *__lock)
{
  return *__lock == 0;
}


#endif /* machine-lock.h */