spinlock.h revision 1.2.2.1
1 1.2.2.1 tls /* $NetBSD: spinlock.h,v 1.2.2.1 2014/08/10 06:55:39 tls Exp $ */ 2 1.2 riastrad 3 1.2 riastrad /*- 4 1.2 riastrad * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 1.2 riastrad * All rights reserved. 6 1.2 riastrad * 7 1.2 riastrad * This code is derived from software contributed to The NetBSD Foundation 8 1.2 riastrad * by Taylor R. Campbell. 9 1.2 riastrad * 10 1.2 riastrad * Redistribution and use in source and binary forms, with or without 11 1.2 riastrad * modification, are permitted provided that the following conditions 12 1.2 riastrad * are met: 13 1.2 riastrad * 1. Redistributions of source code must retain the above copyright 14 1.2 riastrad * notice, this list of conditions and the following disclaimer. 15 1.2 riastrad * 2. Redistributions in binary form must reproduce the above copyright 16 1.2 riastrad * notice, this list of conditions and the following disclaimer in the 17 1.2 riastrad * documentation and/or other materials provided with the distribution. 18 1.2 riastrad * 19 1.2 riastrad * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 1.2 riastrad * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 1.2 riastrad * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 1.2 riastrad * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 1.2 riastrad * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 1.2 riastrad * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 1.2 riastrad * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 1.2 riastrad * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 1.2 riastrad * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 1.2 riastrad * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 1.2 riastrad * POSSIBILITY OF SUCH DAMAGE. 30 1.2 riastrad */ 31 1.2 riastrad 32 1.2 riastrad #ifndef _LINUX_SPINLOCK_H_ 33 1.2 riastrad #define _LINUX_SPINLOCK_H_ 34 1.2 riastrad 35 1.2 riastrad #include <sys/cdefs.h> 36 1.2 riastrad #include <sys/mutex.h> 37 1.2 riastrad 38 1.2 riastrad typedef struct spinlock { 39 1.2 riastrad kmutex_t sl_lock; 40 1.2 riastrad } spinlock_t; 41 1.2 riastrad 42 1.2 riastrad static inline int 43 1.2 riastrad spin_is_locked(spinlock_t *spinlock) 44 1.2 riastrad { 45 1.2 riastrad return mutex_owned(&spinlock->sl_lock); 46 1.2 riastrad } 47 1.2 riastrad 48 1.2 riastrad static inline void 49 1.2 riastrad spin_lock(spinlock_t *spinlock) 50 1.2 riastrad { 51 1.2 riastrad mutex_enter(&spinlock->sl_lock); 52 1.2 riastrad } 53 1.2 riastrad 54 1.2 riastrad static inline void 55 1.2 riastrad spin_unlock(spinlock_t *spinlock) 56 1.2 riastrad { 57 1.2 riastrad mutex_exit(&spinlock->sl_lock); 58 1.2 riastrad } 59 1.2 riastrad 60 1.2 riastrad static inline void 61 1.2 riastrad spin_lock_irq(spinlock_t *spinlock) 62 1.2 riastrad { 63 1.2 riastrad spin_lock(spinlock); 64 1.2 riastrad } 65 1.2 riastrad 66 1.2 riastrad static inline void 67 1.2 riastrad spin_unlock_irq(spinlock_t *spinlock) 68 1.2 riastrad { 69 1.2 riastrad spin_unlock(spinlock); 70 1.2 riastrad } 71 1.2 riastrad 72 1.2 riastrad /* Must be a macro because the second argument is to be assigned. */ 73 1.2 riastrad #define spin_lock_irqsave(SPINLOCK, FLAGS) \ 74 1.2 riastrad do { \ 75 1.2 riastrad (FLAGS) = 0; \ 76 1.2 riastrad mutex_enter(&((spinlock_t *)(SPINLOCK))->sl_lock); \ 77 1.2 riastrad } while (0) 78 1.2 riastrad 79 1.2 riastrad static inline void 80 1.2 riastrad spin_unlock_irqrestore(spinlock_t *spinlock, unsigned long __unused flags) 81 1.2 riastrad { 82 1.2 riastrad mutex_exit(&spinlock->sl_lock); 83 1.2 riastrad } 84 1.2 riastrad 85 1.2 riastrad static inline void 86 1.2 riastrad spin_lock_init(spinlock_t *spinlock) 87 1.2 riastrad { 88 1.2 riastrad /* XXX What's the right IPL? IPL_DRM...? */ 89 1.2 riastrad mutex_init(&spinlock->sl_lock, MUTEX_DEFAULT, IPL_VM); 90 1.2 riastrad } 91 1.2 riastrad 92 1.2 riastrad /* 93 1.2 riastrad * XXX Linux doesn't ever destroy spin locks, it seems. We'll have to 94 1.2 riastrad * kludge it up. 95 1.2 riastrad */ 96 1.2 riastrad 97 1.2 riastrad static inline void 98 1.2 riastrad spin_lock_destroy(spinlock_t *spinlock) 99 1.2 riastrad { 100 1.2 riastrad mutex_destroy(&spinlock->sl_lock); 101 1.2 riastrad } 102 1.2 riastrad 103 1.2 riastrad /* This is a macro to make the panic message clearer. */ 104 1.2 riastrad #define assert_spin_locked(spinlock) \ 105 1.2 riastrad KASSERT(mutex_owned(&(spinlock)->sl_lock)) 106 1.2 riastrad 107 1.2.2.1 tls /* 108 1.2.2.1 tls * Linux rwlocks are reader/writer spin locks. We implement them as 109 1.2.2.1 tls * normal spin locks without reader/writer semantics for expedience. 110 1.2.2.1 tls * If that turns out to not work, adapting to reader/writer semantics 111 1.2.2.1 tls * shouldn't be too hard. 112 1.2.2.1 tls */ 113 1.2.2.1 tls 114 1.2.2.1 tls #define rwlock_t spinlock_t 115 1.2.2.1 tls #define rwlock_init spin_lock_init 116 1.2.2.1 tls #define rwlock_destroy spin_lock_destroy 117 1.2.2.1 tls #define write_lock_irq spin_lock_irq 118 1.2.2.1 tls #define write_unlock_irq spin_unlock_irq 119 1.2.2.1 tls #define read_lock spin_lock 120 1.2.2.1 tls #define read_unlock spin_unlock 121 1.2.2.1 tls 122 1.2 riastrad #endif /* _LINUX_SPINLOCK_H_ */ 123
Indexes created Thu Oct 02 14:10:14 GMT 2025