xref: /openbsd/sys/arch/powerpc/include/mplock.h (revision 9b7c3dbb)
1 /*	$OpenBSD: mplock.h,v 1.2 2015/06/26 11:22:12 dlg Exp $	*/
2 
3 /*
4  * Copyright (c) 2004 Niklas Hallqvist.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #ifndef _POWERPC_MPLOCK_H_
28 #define _POWERPC_MPLOCK_H_
29 
30 /*
31  * Really simple spinlock implementation with recursive capabilities.
32  * Correctness is paramount, no fancyness allowed.
33  */
34 
35 struct __mp_lock {
36 	volatile struct cpu_info *mpl_cpu;
37 	volatile long		mpl_count;
38 };
39 
40 #ifndef _LOCORE
41 
42 void __mp_lock_init(struct __mp_lock *);
43 void __mp_lock(struct __mp_lock *);
44 void __mp_unlock(struct __mp_lock *);
45 int __mp_release_all(struct __mp_lock *);
46 int __mp_release_all_but_one(struct __mp_lock *);
47 void __mp_acquire_count(struct __mp_lock *, int);
48 int __mp_lock_held(struct __mp_lock *);
49 
50 #endif
51 
52 #endif /* !_POWERPC_MPLOCK_H */
53