lock.h revision 1.6 1 1.6 christos /* $NetBSD: lock.h,v 1.6 2017/09/17 00:01:07 christos Exp $ */
2 1.1 cherry
3 1.1 cherry /*-
4 1.1 cherry * Copyright (c) 2000 The NetBSD Foundation, Inc.
5 1.1 cherry * All rights reserved.
6 1.1 cherry *
7 1.1 cherry * This code is derived from software contributed to The NetBSD Foundation
8 1.1 cherry * by Jason R. Thorpe.
9 1.1 cherry *
10 1.1 cherry * Redistribution and use in source and binary forms, with or without
11 1.1 cherry * modification, are permitted provided that the following conditions
12 1.1 cherry * are met:
13 1.1 cherry * 1. Redistributions of source code must retain the above copyright
14 1.1 cherry * notice, this list of conditions and the following disclaimer.
15 1.1 cherry * 2. Redistributions in binary form must reproduce the above copyright
16 1.1 cherry * notice, this list of conditions and the following disclaimer in the
17 1.1 cherry * documentation and/or other materials provided with the distribution.
18 1.1 cherry *
19 1.1 cherry * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 1.1 cherry * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 1.1 cherry * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 1.1 cherry * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 1.1 cherry * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 1.1 cherry * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 1.1 cherry * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 1.1 cherry * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 1.1 cherry * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 1.1 cherry * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 1.1 cherry * POSSIBILITY OF SUCH DAMAGE.
30 1.1 cherry */
31 1.1 cherry
32 1.1 cherry /*
33 1.1 cherry * Machine-dependent spin lock operations.
34 1.1 cherry */
35 1.1 cherry
36 1.1 cherry #ifndef _IA64_LOCK_H_
37 1.1 cherry #define _IA64_LOCK_H_
38 1.1 cherry
39 1.2 kochi static __inline int
40 1.6 christos __SIMPLELOCK_LOCKED_P(const __cpu_simple_lock_t *__ptr)
41 1.2 kochi {
42 1.2 kochi return *__ptr == __SIMPLELOCK_LOCKED;
43 1.2 kochi }
44 1.2 kochi
45 1.2 kochi static __inline int
46 1.6 christos __SIMPLELOCK_UNLOCKED_P(const __cpu_simple_lock_t *__ptr)
47 1.2 kochi {
48 1.2 kochi return *__ptr == __SIMPLELOCK_UNLOCKED;
49 1.2 kochi }
50 1.2 kochi
51 1.2 kochi static __inline void
52 1.2 kochi __cpu_simple_lock_set(__cpu_simple_lock_t *__ptr)
53 1.2 kochi {
54 1.2 kochi
55 1.2 kochi *__ptr = __SIMPLELOCK_LOCKED;
56 1.2 kochi }
57 1.2 kochi
58 1.2 kochi static __inline void
59 1.2 kochi __cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr)
60 1.2 kochi {
61 1.2 kochi
62 1.2 kochi *__ptr = __SIMPLELOCK_UNLOCKED;
63 1.2 kochi }
64 1.2 kochi
65 1.2 kochi #ifdef _KERNEL
66 1.2 kochi
67 1.2 kochi #define SPINLOCK_SPIN_HOOK /* nothing */
68 1.2 kochi #define SPINLOCK_BACKOFF_HOOK /* XXX(kochi): hint@pause */
69 1.2 kochi
70 1.2 kochi #endif
71 1.2 kochi
72 1.2 kochi static __inline void __cpu_simple_lock_init(__cpu_simple_lock_t *)
73 1.2 kochi __unused;
74 1.2 kochi static __inline void __cpu_simple_lock(__cpu_simple_lock_t *)
75 1.2 kochi __unused;
76 1.2 kochi static __inline int __cpu_simple_lock_try(__cpu_simple_lock_t *)
77 1.2 kochi __unused;
78 1.2 kochi static __inline void __cpu_simple_unlock(__cpu_simple_lock_t *)
79 1.2 kochi __unused;
80 1.2 kochi
81 1.2 kochi static __inline void
82 1.2 kochi __cpu_simple_lock_init(__cpu_simple_lock_t *lockp)
83 1.2 kochi {
84 1.2 kochi
85 1.2 kochi *lockp = __SIMPLELOCK_UNLOCKED;
86 1.2 kochi __insn_barrier();
87 1.2 kochi }
88 1.2 kochi
89 1.2 kochi static __inline int
90 1.2 kochi __cpu_simple_lock_try(__cpu_simple_lock_t *lockp)
91 1.2 kochi {
92 1.2 kochi uint8_t val;
93 1.2 kochi
94 1.2 kochi val = __SIMPLELOCK_LOCKED;
95 1.4 kiyohara __asm volatile ("xchg1 %0=[%1],%2" :
96 1.2 kochi "=r" (val)
97 1.4 kiyohara :"r" (lockp), "r" (val)
98 1.4 kiyohara :"memory");
99 1.2 kochi return val == __SIMPLELOCK_UNLOCKED;
100 1.2 kochi }
101 1.2 kochi
102 1.2 kochi static __inline void
103 1.2 kochi __cpu_simple_lock(__cpu_simple_lock_t *lockp)
104 1.2 kochi {
105 1.2 kochi
106 1.2 kochi while (!__cpu_simple_lock_try(lockp))
107 1.2 kochi /* nothing */;
108 1.2 kochi __insn_barrier();
109 1.2 kochi }
110 1.2 kochi
111 1.2 kochi static __inline void
112 1.2 kochi __cpu_simple_unlock(__cpu_simple_lock_t *lockp)
113 1.2 kochi {
114 1.2 kochi
115 1.2 kochi __insn_barrier();
116 1.2 kochi *lockp = __SIMPLELOCK_UNLOCKED;
117 1.2 kochi }
118 1.1 cherry
119 1.5 scole /* XXX mf.a overkill for these? */
120 1.5 scole static __inline void
121 1.5 scole mb_read(void)
122 1.5 scole {
123 1.5 scole __asm __volatile("mf.a \n"
124 1.5 scole "mf \n" ::: "memory");
125 1.5 scole }
126 1.5 scole
127 1.5 scole static __inline void
128 1.5 scole mb_write(void)
129 1.5 scole {
130 1.5 scole __asm __volatile("mf.a \n"
131 1.5 scole "mf \n" ::: "memory");
132 1.5 scole }
133 1.5 scole
134 1.5 scole static __inline void
135 1.5 scole mb_memory(void)
136 1.5 scole {
137 1.5 scole __asm __volatile("mf.a \n"
138 1.5 scole "mf \n" ::: "memory");
139 1.5 scole }
140 1.5 scole
141 1.1 cherry #endif /* _IA64_LOCK_H_ */
142