lock.h revision 1.6 1 /* $NetBSD: lock.h,v 1.6 2001/06/03 15:10:11 ragge Exp $ */
2
3 /*
4 * Copyright (c) 2000 Ludd, University of Lule}, Sweden.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed at Ludd, University of Lule}.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #ifndef _VAX_LOCK_H_
34 #define _VAX_LOCK_H_
35
36 typedef __volatile int __cpu_simple_lock_t;
37
38 #define __SIMPLELOCK_LOCKED 1
39 #define __SIMPLELOCK_UNLOCKED 0
40
41 static __inline void
42 __cpu_simple_lock_init(__cpu_simple_lock_t *alp)
43 {
44 __asm__ __volatile ("movl %0,r1;jsb Sunlock"
45 : /* No output */
46 : "g"(alp)
47 : "r1","cc","memory");
48 #if 0
49 __asm__ __volatile ("bbcci $0, %0, 1f;1:"
50 : /* No output */
51 : "m"(*alp));
52 #endif
53 }
54
55 static __inline void
56 __cpu_simple_lock(__cpu_simple_lock_t *alp)
57 {
58 __asm__ __volatile ("movl %0,r1;jsb Slock"
59 : /* No output */
60 : "g"(alp)
61 : "r0","r1","cc","memory");
62 #if 0
63 __asm__ __volatile ("1:;bbssi $0, %0, 1b"
64 : /* No output */
65 : "m"(*alp));
66 #endif
67 }
68
69 static __inline void
70 __cpu_simple_unlock(__cpu_simple_lock_t *alp)
71 {
72 __asm__ __volatile ("movl %0,r1;jsb Sunlock"
73 : /* No output */
74 : "g"(alp)
75 : "r1","cc","memory");
76 #if 0
77 __asm__ __volatile ("bbcci $0, %0, 1f;1:"
78 : /* No output */
79 : "m"(*alp));
80 #endif
81 }
82
83 static __inline int
84 __cpu_simple_lock_try(__cpu_simple_lock_t *alp)
85 {
86 int ret;
87
88 __asm__ __volatile ("movl %1,r1;jsb Slocktry;movl r0,%0"
89 : "=&r"(ret)
90 : "g"(alp)
91 : "r0","r1","cc","memory");
92 #if 0
93 __asm__ __volatile ("movl $0,%0;bbssi $0,%1,1f;incl %0;1:"
94 : "=&r"(ret)
95 : "m"(*alp));
96 #endif
97
98 return ret;
99 }
100
101 #if defined(MULTIPROCESSOR)
102 /*
103 * On the Vax, interprocessor interrupts can come in at device priority
104 * level or lower. This can cause some problems while waiting for r/w
105 * spinlocks from a high'ish priority level: IPIs that come in will not
106 * be processed. This can lead to deadlock.
107 *
108 * This hook allows IPIs to be processed while a spinlock's interlock
109 * is released.
110 */
111 #define SPINLOCK_SPIN_HOOK \
112 do { \
113 struct cpu_info *__ci = curcpu(); \
114 \
115 if (__ci->ci_ipimsgs != 0) { \
116 /* printf("CPU %lu has IPIs pending\n", \
117 __ci->ci_cpuid); */ \
118 cpu_handle_ipi(); \
119 } \
120 } while (0)
121 #endif /* MULTIPROCESSOR */
122 #endif /* _VAX_LOCK_H_ */
123