| 1 | /* $Id: lock.h 43363 2012-09-20 09:56:07Z vboxsync $ */
|
|---|
| 2 | /** @file
|
|---|
| 3 | * Lock.h - Haiku, private locking internals.
|
|---|
| 4 | */
|
|---|
| 5 |
|
|---|
| 6 | /*
|
|---|
| 7 | * Copyright (C) 2012 Oracle Corporation
|
|---|
| 8 | *
|
|---|
| 9 | * This file is part of VirtualBox Open Source Edition (OSE), as
|
|---|
| 10 | * available from http://www.virtualbox.org. This file is free software;
|
|---|
| 11 | * you can redistribute it and/or modify it under the terms of the GNU
|
|---|
| 12 | * General Public License (GPL) as published by the Free Software
|
|---|
| 13 | * Foundation, in version 2 as it comes in the "COPYING" file of the
|
|---|
| 14 | * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
|
|---|
| 15 | * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
|
|---|
| 16 | */
|
|---|
| 17 |
|
|---|
| 18 | /*
|
|---|
| 19 | * This code is based on:
|
|---|
| 20 | *
|
|---|
| 21 | * VirtualBox Guest Additions for Haiku.
|
|---|
| 22 | *
|
|---|
| 23 | * Copyright 2008-2010, Ingo Weinhold, ingo_weinhold@gmx.de.
|
|---|
| 24 | * Copyright 2002-2009, Axel Dörfler, axeld@pinc-software.de.
|
|---|
| 25 | * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
|
|---|
| 26 | * Distributed under the terms of the MIT License.
|
|---|
| 27 | */
|
|---|
| 28 |
|
|---|
| 29 | /** @todo r=ramshankar: Eventually this file should be shipped by Haiku and
|
|---|
| 30 | * should be removed from the VBox tree. */
|
|---|
| 31 |
|
|---|
| 32 | #ifndef _KERNEL_LOCK_H
|
|---|
| 33 | #define _KERNEL_LOCK_H
|
|---|
| 34 |
|
|---|
| 35 | #include <OS.h>
|
|---|
| 36 |
|
|---|
| 37 |
|
|---|
| 38 | struct mutex_waiter;
|
|---|
| 39 |
|
|---|
| 40 | typedef struct mutex {
|
|---|
| 41 | const char* name;
|
|---|
| 42 | struct mutex_waiter* waiters;
|
|---|
| 43 | #if KDEBUG
|
|---|
| 44 | thread_id holder;
|
|---|
| 45 | #else
|
|---|
| 46 | int32 count;
|
|---|
| 47 | uint16 ignore_unlock_count;
|
|---|
| 48 | #endif
|
|---|
| 49 | uint8 flags;
|
|---|
| 50 | } mutex;
|
|---|
| 51 |
|
|---|
| 52 | #define MUTEX_FLAG_CLONE_NAME 0x1
|
|---|
| 53 |
|
|---|
| 54 |
|
|---|
| 55 | typedef struct recursive_lock {
|
|---|
| 56 | mutex lock;
|
|---|
| 57 | #if !KDEBUG
|
|---|
| 58 | thread_id holder;
|
|---|
| 59 | #endif
|
|---|
| 60 | int recursion;
|
|---|
| 61 | } recursive_lock;
|
|---|
| 62 |
|
|---|
| 63 |
|
|---|
| 64 | struct rw_lock_waiter;
|
|---|
| 65 |
|
|---|
| 66 | typedef struct rw_lock {
|
|---|
| 67 | const char* name;
|
|---|
| 68 | struct rw_lock_waiter* waiters;
|
|---|
| 69 | thread_id holder;
|
|---|
| 70 | vint32 count;
|
|---|
| 71 | int32 owner_count;
|
|---|
| 72 | int16 active_readers;
|
|---|
| 73 | // Only > 0 while a writer is waiting: number
|
|---|
| 74 | // of active readers when the first waiting
|
|---|
| 75 | // writer started waiting.
|
|---|
| 76 | int16 pending_readers;
|
|---|
| 77 | // Number of readers that have already
|
|---|
| 78 | // incremented "count", but have not yet started
|
|---|
| 79 | // to wait at the time the last writer unlocked.
|
|---|
| 80 | uint32 flags;
|
|---|
| 81 | } rw_lock;
|
|---|
| 82 |
|
|---|
| 83 | #define RW_LOCK_WRITER_COUNT_BASE 0x10000
|
|---|
| 84 |
|
|---|
| 85 | #define RW_LOCK_FLAG_CLONE_NAME 0x1
|
|---|
| 86 |
|
|---|
| 87 |
|
|---|
| 88 | #if KDEBUG
|
|---|
| 89 | # define KDEBUG_RW_LOCK_DEBUG 0
|
|---|
| 90 | // Define to 1 if you want to use ASSERT_READ_LOCKED_RW_LOCK().
|
|---|
| 91 | // The rw_lock will just behave like a recursive locker then.
|
|---|
| 92 | # define ASSERT_LOCKED_RECURSIVE(r) \
|
|---|
| 93 | { ASSERT(find_thread(NULL) == (r)->lock.holder); }
|
|---|
| 94 | # define ASSERT_LOCKED_MUTEX(m) { ASSERT(find_thread(NULL) == (m)->holder); }
|
|---|
| 95 | # define ASSERT_WRITE_LOCKED_RW_LOCK(l) \
|
|---|
| 96 | { ASSERT(find_thread(NULL) == (l)->holder); }
|
|---|
| 97 | # if KDEBUG_RW_LOCK_DEBUG
|
|---|
| 98 | # define ASSERT_READ_LOCKED_RW_LOCK(l) \
|
|---|
| 99 | { ASSERT(find_thread(NULL) == (l)->holder); }
|
|---|
| 100 | # else
|
|---|
| 101 | # define ASSERT_READ_LOCKED_RW_LOCK(l) do {} while (false)
|
|---|
| 102 | # endif
|
|---|
| 103 | #else
|
|---|
| 104 | # define ASSERT_LOCKED_RECURSIVE(r) do {} while (false)
|
|---|
| 105 | # define ASSERT_LOCKED_MUTEX(m) do {} while (false)
|
|---|
| 106 | # define ASSERT_WRITE_LOCKED_RW_LOCK(m) do {} while (false)
|
|---|
| 107 | # define ASSERT_READ_LOCKED_RW_LOCK(l) do {} while (false)
|
|---|
| 108 | #endif
|
|---|
| 109 |
|
|---|
| 110 |
|
|---|
| 111 | // static initializers
|
|---|
| 112 | #if KDEBUG
|
|---|
| 113 | # define MUTEX_INITIALIZER(name) { name, NULL, -1, 0 }
|
|---|
| 114 | # define RECURSIVE_LOCK_INITIALIZER(name) { MUTEX_INITIALIZER(name), 0 }
|
|---|
| 115 | #else
|
|---|
| 116 | # define MUTEX_INITIALIZER(name) { name, NULL, 0, 0, 0 }
|
|---|
| 117 | # define RECURSIVE_LOCK_INITIALIZER(name) { MUTEX_INITIALIZER(name), -1, 0 }
|
|---|
| 118 | #endif
|
|---|
| 119 |
|
|---|
| 120 | #define RW_LOCK_INITIALIZER(name) { name, NULL, -1, 0, 0, 0 }
|
|---|
| 121 |
|
|---|
| 122 |
|
|---|
| 123 | #if KDEBUG
|
|---|
| 124 | # define RECURSIVE_LOCK_HOLDER(recursiveLock) ((recursiveLock)->lock.holder)
|
|---|
| 125 | #else
|
|---|
| 126 | # define RECURSIVE_LOCK_HOLDER(recursiveLock) ((recursiveLock)->holder)
|
|---|
| 127 | #endif
|
|---|
| 128 |
|
|---|
| 129 |
|
|---|
| 130 | #ifdef __cplusplus
|
|---|
| 131 | extern "C" {
|
|---|
| 132 | #endif
|
|---|
| 133 |
|
|---|
| 134 | extern void recursive_lock_init(recursive_lock *lock, const char *name);
|
|---|
| 135 | // name is *not* cloned nor freed in recursive_lock_destroy()
|
|---|
| 136 | extern void recursive_lock_init_etc(recursive_lock *lock, const char *name,
|
|---|
| 137 | uint32 flags);
|
|---|
| 138 | extern void recursive_lock_destroy(recursive_lock *lock);
|
|---|
| 139 | extern status_t recursive_lock_lock(recursive_lock *lock);
|
|---|
| 140 | extern status_t recursive_lock_trylock(recursive_lock *lock);
|
|---|
| 141 | extern void recursive_lock_unlock(recursive_lock *lock);
|
|---|
| 142 | extern int32 recursive_lock_get_recursion(recursive_lock *lock);
|
|---|
| 143 |
|
|---|
| 144 | extern void rw_lock_init(rw_lock* lock, const char* name);
|
|---|
| 145 | // name is *not* cloned nor freed in rw_lock_destroy()
|
|---|
| 146 | extern void rw_lock_init_etc(rw_lock* lock, const char* name, uint32 flags);
|
|---|
| 147 | extern void rw_lock_destroy(rw_lock* lock);
|
|---|
| 148 | extern status_t rw_lock_write_lock(rw_lock* lock);
|
|---|
| 149 |
|
|---|
| 150 | extern void mutex_init(mutex* lock, const char* name);
|
|---|
| 151 | // name is *not* cloned nor freed in mutex_destroy()
|
|---|
| 152 | extern void mutex_init_etc(mutex* lock, const char* name, uint32 flags);
|
|---|
| 153 | extern void mutex_destroy(mutex* lock);
|
|---|
| 154 | extern status_t mutex_switch_lock(mutex* from, mutex* to);
|
|---|
| 155 | // Unlocks "from" and locks "to" such that unlocking and starting to wait
|
|---|
| 156 | // for the lock is atomically. I.e. if "from" guards the object "to" belongs
|
|---|
| 157 | // to, the operation is safe as long as "from" is held while destroying
|
|---|
| 158 | // "to".
|
|---|
| 159 | extern status_t mutex_switch_from_read_lock(rw_lock* from, mutex* to);
|
|---|
| 160 | // Like mutex_switch_lock(), just for a switching from a read-locked
|
|---|
| 161 | // rw_lock.
|
|---|
| 162 |
|
|---|
| 163 |
|
|---|
| 164 | // implementation private:
|
|---|
| 165 |
|
|---|
| 166 | extern status_t _rw_lock_read_lock(rw_lock* lock);
|
|---|
| 167 | extern status_t _rw_lock_read_lock_with_timeout(rw_lock* lock,
|
|---|
| 168 | uint32 timeoutFlags, bigtime_t timeout);
|
|---|
| 169 | extern void _rw_lock_read_unlock(rw_lock* lock, bool threadsLocked);
|
|---|
| 170 | extern void _rw_lock_write_unlock(rw_lock* lock, bool threadsLocked);
|
|---|
| 171 |
|
|---|
| 172 | extern status_t _mutex_lock(mutex* lock, bool threadsLocked);
|
|---|
| 173 | extern void _mutex_unlock(mutex* lock, bool threadsLocked);
|
|---|
| 174 | extern status_t _mutex_trylock(mutex* lock);
|
|---|
| 175 | extern status_t _mutex_lock_with_timeout(mutex* lock, uint32 timeoutFlags,
|
|---|
| 176 | bigtime_t timeout);
|
|---|
| 177 |
|
|---|
| 178 |
|
|---|
| 179 | static inline status_t
|
|---|
| 180 | rw_lock_read_lock(rw_lock* lock)
|
|---|
| 181 | {
|
|---|
| 182 | #if KDEBUG_RW_LOCK_DEBUG
|
|---|
| 183 | return rw_lock_write_lock(lock);
|
|---|
| 184 | #else
|
|---|
| 185 | int32 oldCount = atomic_add(&lock->count, 1);
|
|---|
| 186 | if (oldCount >= RW_LOCK_WRITER_COUNT_BASE)
|
|---|
| 187 | return _rw_lock_read_lock(lock);
|
|---|
| 188 | return B_OK;
|
|---|
| 189 | #endif
|
|---|
| 190 | }
|
|---|
| 191 |
|
|---|
| 192 |
|
|---|
| 193 | static inline status_t
|
|---|
| 194 | rw_lock_read_lock_with_timeout(rw_lock* lock, uint32 timeoutFlags,
|
|---|
| 195 | bigtime_t timeout)
|
|---|
| 196 | {
|
|---|
| 197 | #if KDEBUG_RW_LOCK_DEBUG
|
|---|
| 198 | return mutex_lock_with_timeout(lock, timeoutFlags, timeout);
|
|---|
| 199 | #else
|
|---|
| 200 | int32 oldCount = atomic_add(&lock->count, 1);
|
|---|
| 201 | if (oldCount >= RW_LOCK_WRITER_COUNT_BASE)
|
|---|
| 202 | return _rw_lock_read_lock_with_timeout(lock, timeoutFlags, timeout);
|
|---|
| 203 | return B_OK;
|
|---|
| 204 | #endif
|
|---|
| 205 | }
|
|---|
| 206 |
|
|---|
| 207 |
|
|---|
| 208 | static inline void
|
|---|
| 209 | rw_lock_read_unlock(rw_lock* lock)
|
|---|
| 210 | {
|
|---|
| 211 | #if KDEBUG_RW_LOCK_DEBUG
|
|---|
| 212 | rw_lock_write_unlock(lock);
|
|---|
| 213 | #else
|
|---|
| 214 | int32 oldCount = atomic_add(&lock->count, -1);
|
|---|
| 215 | if (oldCount >= RW_LOCK_WRITER_COUNT_BASE)
|
|---|
| 216 | _rw_lock_read_unlock(lock, false);
|
|---|
| 217 | #endif
|
|---|
| 218 | }
|
|---|
| 219 |
|
|---|
| 220 |
|
|---|
| 221 | static inline void
|
|---|
| 222 | rw_lock_write_unlock(rw_lock* lock)
|
|---|
| 223 | {
|
|---|
| 224 | _rw_lock_write_unlock(lock, false);
|
|---|
| 225 | }
|
|---|
| 226 |
|
|---|
| 227 |
|
|---|
| 228 | static inline status_t
|
|---|
| 229 | mutex_lock(mutex* lock)
|
|---|
| 230 | {
|
|---|
| 231 | #if KDEBUG
|
|---|
| 232 | return _mutex_lock(lock, false);
|
|---|
| 233 | #else
|
|---|
| 234 | if (atomic_add(&lock->count, -1) < 0)
|
|---|
| 235 | return _mutex_lock(lock, false);
|
|---|
| 236 | return B_OK;
|
|---|
| 237 | #endif
|
|---|
| 238 | }
|
|---|
| 239 |
|
|---|
| 240 |
|
|---|
| 241 | static inline status_t
|
|---|
| 242 | mutex_lock_threads_locked(mutex* lock)
|
|---|
| 243 | {
|
|---|
| 244 | #if KDEBUG
|
|---|
| 245 | return _mutex_lock(lock, true);
|
|---|
| 246 | #else
|
|---|
| 247 | if (atomic_add(&lock->count, -1) < 0)
|
|---|
| 248 | return _mutex_lock(lock, true);
|
|---|
| 249 | return B_OK;
|
|---|
| 250 | #endif
|
|---|
| 251 | }
|
|---|
| 252 |
|
|---|
| 253 |
|
|---|
| 254 | static inline status_t
|
|---|
| 255 | mutex_trylock(mutex* lock)
|
|---|
| 256 | {
|
|---|
| 257 | #if KDEBUG
|
|---|
| 258 | return _mutex_trylock(lock);
|
|---|
| 259 | #else
|
|---|
| 260 | if (atomic_test_and_set(&lock->count, -1, 0) != 0)
|
|---|
| 261 | return B_WOULD_BLOCK;
|
|---|
| 262 | return B_OK;
|
|---|
| 263 | #endif
|
|---|
| 264 | }
|
|---|
| 265 |
|
|---|
| 266 |
|
|---|
| 267 | static inline status_t
|
|---|
| 268 | mutex_lock_with_timeout(mutex* lock, uint32 timeoutFlags, bigtime_t timeout)
|
|---|
| 269 | {
|
|---|
| 270 | #if KDEBUG
|
|---|
| 271 | return _mutex_lock_with_timeout(lock, timeoutFlags, timeout);
|
|---|
| 272 | #else
|
|---|
| 273 | if (atomic_add(&lock->count, -1) < 0)
|
|---|
| 274 | return _mutex_lock_with_timeout(lock, timeoutFlags, timeout);
|
|---|
| 275 | return B_OK;
|
|---|
| 276 | #endif
|
|---|
| 277 | }
|
|---|
| 278 |
|
|---|
| 279 |
|
|---|
| 280 | static inline void
|
|---|
| 281 | mutex_unlock(mutex* lock)
|
|---|
| 282 | {
|
|---|
| 283 | #if !KDEBUG
|
|---|
| 284 | if (atomic_add(&lock->count, 1) < -1)
|
|---|
| 285 | #endif
|
|---|
| 286 | _mutex_unlock(lock, false);
|
|---|
| 287 | }
|
|---|
| 288 |
|
|---|
| 289 |
|
|---|
| 290 | static inline void
|
|---|
| 291 | mutex_transfer_lock(mutex* lock, thread_id thread)
|
|---|
| 292 | {
|
|---|
| 293 | #if KDEBUG
|
|---|
| 294 | lock->holder = thread;
|
|---|
| 295 | #endif
|
|---|
| 296 | }
|
|---|
| 297 |
|
|---|
| 298 |
|
|---|
| 299 | extern void lock_debug_init();
|
|---|
| 300 |
|
|---|
| 301 | #ifdef __cplusplus
|
|---|
| 302 | }
|
|---|
| 303 | #endif
|
|---|
| 304 |
|
|---|
| 305 | #endif /* _KERNEL_LOCK_H */
|
|---|
