1 /*- 2 * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. Berkeley Software Design Inc's name may not be used to endorse or 13 * promote products derived from this software without specific prior 14 * written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * from BSDI Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp 29 * $FreeBSD$ 30 */ 31 32 #ifndef _SYS_LOCK_H_ 33 #define _SYS_LOCK_H_ 34 35 #include <sys/queue.h> 36 #include <sys/_lock.h> 37 38 struct lock_list_entry; 39 struct thread; 40 41 /* 42 * Lock classes. Each lock has a class which describes characteristics 43 * common to all types of locks of a given class. 44 * 45 * Spin locks in general must always protect against preemption, as it is 46 * an error to perform any type of context switch while holding a spin lock. 47 * Also, for an individual lock to be recursable, its class must allow 48 * recursion and the lock itself must explicitly allow recursion. 49 * 50 * The 'lc_ddb_show' function pointer is used to dump class-specific 51 * data for the 'show lock' DDB command. The 'lc_lock' and 52 * 'lc_unlock' function pointers are used in sleep(9) and cv_wait(9) 53 * to lock and unlock locks while blocking on a sleep queue. The 54 * return value of 'lc_unlock' will be passed to 'lc_lock' on resume 55 * to allow communication of state between the two routines. 56 */ 57 58 struct lock_class { 59 const char *lc_name; 60 u_int lc_flags; 61 void (*lc_assert)(const struct lock_object *lock, int what); 62 void (*lc_ddb_show)(const struct lock_object *lock); 63 void (*lc_lock)(struct lock_object *lock, uintptr_t how); 64 int (*lc_owner)(const struct lock_object *lock, 65 struct thread **owner); 66 uintptr_t (*lc_unlock)(struct lock_object *lock); 67 }; 68 69 #define LC_SLEEPLOCK 0x00000001 /* Sleep lock. */ 70 #define LC_SPINLOCK 0x00000002 /* Spin lock. */ 71 #define LC_SLEEPABLE 0x00000004 /* Sleeping allowed with this lock. */ 72 #define LC_RECURSABLE 0x00000008 /* Locks of this type may recurse. */ 73 #define LC_UPGRADABLE 0x00000010 /* Upgrades and downgrades permitted. */ 74 75 #define LO_CLASSFLAGS 0x0000ffff /* Class specific flags. */ 76 #define LO_INITIALIZED 0x00010000 /* Lock has been initialized. */ 77 #define LO_WITNESS 0x00020000 /* Should witness monitor this lock. */ 78 #define LO_QUIET 0x00040000 /* Don't log locking operations. */ 79 #define LO_RECURSABLE 0x00080000 /* Lock may recurse. */ 80 #define LO_SLEEPABLE 0x00100000 /* Lock may be held while sleeping. */ 81 #define LO_UPGRADABLE 0x00200000 /* Lock may be upgraded/downgraded. */ 82 #define LO_DUPOK 0x00400000 /* Don't check for duplicate acquires */ 83 #define LO_IS_VNODE 0x00800000 /* Tell WITNESS about a VNODE lock */ 84 #define LO_CLASSMASK 0x0f000000 /* Class index bitmask. */ 85 #define LO_NOPROFILE 0x10000000 /* Don't profile this lock */ 86 87 /* 88 * Lock classes are statically assigned an index into the gobal lock_classes 89 * array. Debugging code looks up the lock class for a given lock object 90 * by indexing the array. 91 */ 92 #define LO_CLASSSHIFT 24 93 #define LO_CLASSINDEX(lock) ((((lock)->lo_flags) & LO_CLASSMASK) >> LO_CLASSSHIFT) 94 #define LOCK_CLASS(lock) (lock_classes[LO_CLASSINDEX((lock))]) 95 #define LOCK_CLASS_MAX (LO_CLASSMASK >> LO_CLASSSHIFT) 96 97 /* 98 * Option flags passed to lock operations that witness also needs to know 99 * about or that are generic across all locks. 100 */ 101 #define LOP_NEWORDER 0x00000001 /* Define a new lock order. */ 102 #define LOP_QUIET 0x00000002 /* Don't log locking operations. */ 103 #define LOP_TRYLOCK 0x00000004 /* Don't check lock order. */ 104 #define LOP_EXCLUSIVE 0x00000008 /* Exclusive lock. */ 105 #define LOP_DUPOK 0x00000010 /* Don't check for duplicate acquires */ 106 107 /* Flags passed to witness_assert. */ 108 #define LA_MASKASSERT 0x000000ff /* Mask for witness defined asserts. */ 109 #define LA_UNLOCKED 0x00000000 /* Lock is unlocked. */ 110 #define LA_LOCKED 0x00000001 /* Lock is at least share locked. */ 111 #define LA_SLOCKED 0x00000002 /* Lock is exactly share locked. */ 112 #define LA_XLOCKED 0x00000004 /* Lock is exclusively locked. */ 113 #define LA_RECURSED 0x00000008 /* Lock is recursed. */ 114 #define LA_NOTRECURSED 0x00000010 /* Lock is not recursed. */ 115 116 #ifdef _KERNEL 117 /* 118 * If any of WITNESS, INVARIANTS, or KTR_LOCK KTR tracing has been enabled, 119 * then turn on LOCK_DEBUG. When this option is on, extra debugging 120 * facilities such as tracking the file and line number of lock operations 121 * are enabled. Also, mutex locking operations are not inlined to avoid 122 * bloat from all the extra debugging code. We also have to turn on all the 123 * calling conventions for this debugging code in modules so that modules can 124 * work with both debug and non-debug kernels. 125 */ 126 #if defined(KLD_MODULE) || defined(WITNESS) || defined(INVARIANTS) || defined(INVARIANT_SUPPORT) || defined(KTR) || defined(LOCK_PROFILING) 127 #define LOCK_DEBUG 1 128 #else 129 #define LOCK_DEBUG 0 130 #endif 131 132 /* 133 * In the LOCK_DEBUG case, use the filename and line numbers for debugging 134 * operations. Otherwise, use default values to avoid the unneeded bloat. 135 */ 136 #if LOCK_DEBUG > 0 137 #define LOCK_FILE __FILE__ 138 #define LOCK_LINE __LINE__ 139 #else 140 #define LOCK_FILE NULL 141 #define LOCK_LINE 0 142 #endif 143 144 /* 145 * Macros for KTR_LOCK tracing. 146 * 147 * opname - name of this operation (LOCK/UNLOCK/SLOCK, etc.) 148 * lo - struct lock_object * for this lock 149 * flags - flags passed to the lock operation 150 * recurse - this locks recursion level (or 0 if class is not recursable) 151 * result - result of a try lock operation 152 * file - file name 153 * line - line number 154 */ 155 #define LOCK_LOG_TEST(lo, flags) \ 156 (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0) 157 158 #define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do { \ 159 if (LOCK_LOG_TEST((lo), (flags))) \ 160 CTR6(KTR_LOCK, opname " (%s) %s %p r = %d at %s:%d", \ 161 LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ 162 (lo), (u_int)(recurse), (file), (line)); \ 163 } while (0) 164 165 #define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do { \ 166 if (LOCK_LOG_TEST((lo), (flags))) \ 167 CTR6(KTR_LOCK, "TRY_" opname " (%s) %s %p result=%d at %s:%d",\ 168 LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ 169 (lo), (u_int)(result), (file), (line)); \ 170 } while (0) 171 172 #define LOCK_LOG_INIT(lo, flags) do { \ 173 if (LOCK_LOG_TEST((lo), (flags))) \ 174 CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo), \ 175 LOCK_CLASS(lo)->lc_name, (lo)->lo_name); \ 176 } while (0) 177 178 #define LOCK_LOG_DESTROY(lo, flags) LOCK_LOG_INIT(lo, flags) 179 180 #define lock_initalized(lo) ((lo)->lo_flags & LO_INITIALIZED) 181 182 /* 183 * Helpful macros for quickly coming up with assertions with informative 184 * panic messages. 185 */ 186 #define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) 187 #define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) 188 #define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) 189 #define MPASS4(ex, what, file, line) \ 190 KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) 191 192 extern struct lock_class lock_class_mtx_sleep; 193 extern struct lock_class lock_class_mtx_spin; 194 extern struct lock_class lock_class_sx; 195 extern struct lock_class lock_class_rw; 196 extern struct lock_class lock_class_rm; 197 extern struct lock_class lock_class_rm_sleepable; 198 extern struct lock_class lock_class_lockmgr; 199 200 extern struct lock_class *lock_classes[]; 201 202 void lock_init(struct lock_object *, struct lock_class *, 203 const char *, const char *, int); 204 void lock_destroy(struct lock_object *); 205 void spinlock_enter(void); 206 void spinlock_exit(void); 207 void witness_init(struct lock_object *, const char *); 208 void witness_destroy(struct lock_object *); 209 int witness_defineorder(struct lock_object *, struct lock_object *); 210 void witness_checkorder(struct lock_object *, int, const char *, int, 211 struct lock_object *); 212 void witness_lock(struct lock_object *, int, const char *, int); 213 void witness_upgrade(struct lock_object *, int, const char *, int); 214 void witness_downgrade(struct lock_object *, int, const char *, int); 215 void witness_unlock(struct lock_object *, int, const char *, int); 216 void witness_save(struct lock_object *, const char **, int *); 217 void witness_restore(struct lock_object *, const char *, int); 218 int witness_list_locks(struct lock_list_entry **, 219 int (*)(const char *, ...)); 220 int witness_warn(int, struct lock_object *, const char *, ...); 221 void witness_assert(const struct lock_object *, int, const char *, int); 222 void witness_display_spinlock(struct lock_object *, struct thread *, 223 int (*)(const char *, ...)); 224 int witness_line(struct lock_object *); 225 void witness_norelease(struct lock_object *); 226 void witness_releaseok(struct lock_object *); 227 const char *witness_file(struct lock_object *); 228 void witness_thread_exit(struct thread *); 229 230 #ifdef WITNESS 231 232 /* Flags for witness_warn(). */ 233 #define WARN_GIANTOK 0x01 /* Giant is exempt from this check. */ 234 #define WARN_PANIC 0x02 /* Panic if check fails. */ 235 #define WARN_SLEEPOK 0x04 /* Sleepable locks are exempt from check. */ 236 237 #define WITNESS_INIT(lock, type) \ 238 witness_init((lock), (type)) 239 240 #define WITNESS_DESTROY(lock) \ 241 witness_destroy(lock) 242 243 #define WITNESS_CHECKORDER(lock, flags, file, line, interlock) \ 244 witness_checkorder((lock), (flags), (file), (line), (interlock)) 245 246 #define WITNESS_DEFINEORDER(lock1, lock2) \ 247 witness_defineorder((struct lock_object *)(lock1), \ 248 (struct lock_object *)(lock2)) 249 250 #define WITNESS_LOCK(lock, flags, file, line) \ 251 witness_lock((lock), (flags), (file), (line)) 252 253 #define WITNESS_UPGRADE(lock, flags, file, line) \ 254 witness_upgrade((lock), (flags), (file), (line)) 255 256 #define WITNESS_DOWNGRADE(lock, flags, file, line) \ 257 witness_downgrade((lock), (flags), (file), (line)) 258 259 #define WITNESS_UNLOCK(lock, flags, file, line) \ 260 witness_unlock((lock), (flags), (file), (line)) 261 262 #define WITNESS_CHECK(flags, lock, fmt, ...) \ 263 witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) 264 265 #define WITNESS_WARN(flags, lock, fmt, ...) \ 266 witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) 267 268 #define WITNESS_SAVE_DECL(n) \ 269 const char * __CONCAT(n, __wf); \ 270 int __CONCAT(n, __wl) 271 272 #define WITNESS_SAVE(lock, n) \ 273 witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl)) 274 275 #define WITNESS_RESTORE(lock, n) \ 276 witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl)) 277 278 #define WITNESS_NORELEASE(lock) \ 279 witness_norelease(&(lock)->lock_object) 280 281 #define WITNESS_RELEASEOK(lock) \ 282 witness_releaseok(&(lock)->lock_object) 283 284 #define WITNESS_FILE(lock) \ 285 witness_file(lock) 286 287 #define WITNESS_LINE(lock) \ 288 witness_line(lock) 289 290 #else /* WITNESS */ 291 #define WITNESS_INIT(lock, type) (void)0 292 #define WITNESS_DESTROY(lock) (void)0 293 #define WITNESS_DEFINEORDER(lock1, lock2) 0 294 #define WITNESS_CHECKORDER(lock, flags, file, line, interlock) (void)0 295 #define WITNESS_LOCK(lock, flags, file, line) (void)0 296 #define WITNESS_UPGRADE(lock, flags, file, line) (void)0 297 #define WITNESS_DOWNGRADE(lock, flags, file, line) (void)0 298 #define WITNESS_UNLOCK(lock, flags, file, line) (void)0 299 #define WITNESS_CHECK(flags, lock, fmt, ...) 0 300 #define WITNESS_WARN(flags, lock, fmt, ...) (void)0 301 #define WITNESS_SAVE_DECL(n) (void)0 302 #define WITNESS_SAVE(lock, n) (void)0 303 #define WITNESS_RESTORE(lock, n) (void)0 304 #define WITNESS_NORELEASE(lock) (void)0 305 #define WITNESS_RELEASEOK(lock) (void)0 306 #define WITNESS_FILE(lock) ("?") 307 #define WITNESS_LINE(lock) (0) 308 #endif /* WITNESS */ 309 310 #endif /* _KERNEL */ 311 #endif /* _SYS_LOCK_H_ */ 312