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 #include <sys/ktr_class.h> 38 39 struct lock_list_entry; 40 struct thread; 41 42 /* 43 * Lock classes. Each lock has a class which describes characteristics 44 * common to all types of locks of a given class. 45 * 46 * Spin locks in general must always protect against preemption, as it is 47 * an error to perform any type of context switch while holding a spin lock. 48 * Also, for an individual lock to be recursable, its class must allow 49 * recursion and the lock itself must explicitly allow recursion. 50 * 51 * The 'lc_ddb_show' function pointer is used to dump class-specific 52 * data for the 'show lock' DDB command. The 'lc_lock' and 53 * 'lc_unlock' function pointers are used in sleep(9) and cv_wait(9) 54 * to lock and unlock locks while blocking on a sleep queue. The 55 * return value of 'lc_unlock' will be passed to 'lc_lock' on resume 56 * to allow communication of state between the two routines. 57 */ 58 59 struct lock_class { 60 const char *lc_name; 61 u_int lc_flags; 62 void (*lc_assert)(const struct lock_object *lock, int what); 63 void (*lc_ddb_show)(const struct lock_object *lock); 64 void (*lc_lock)(struct lock_object *lock, uintptr_t how); 65 int (*lc_owner)(const struct lock_object *lock, 66 struct thread **owner); 67 uintptr_t (*lc_unlock)(struct lock_object *lock); 68 }; 69 70 #define LC_SLEEPLOCK 0x00000001 /* Sleep lock. */ 71 #define LC_SPINLOCK 0x00000002 /* Spin lock. */ 72 #define LC_SLEEPABLE 0x00000004 /* Sleeping allowed with this lock. */ 73 #define LC_RECURSABLE 0x00000008 /* Locks of this type may recurse. */ 74 #define LC_UPGRADABLE 0x00000010 /* Upgrades and downgrades permitted. */ 75 76 #define LO_CLASSFLAGS 0x0000ffff /* Class specific flags. */ 77 #define LO_INITIALIZED 0x00010000 /* Lock has been initialized. */ 78 #define LO_WITNESS 0x00020000 /* Should witness monitor this lock. */ 79 #define LO_QUIET 0x00040000 /* Don't log locking operations. */ 80 #define LO_RECURSABLE 0x00080000 /* Lock may recurse. */ 81 #define LO_SLEEPABLE 0x00100000 /* Lock may be held while sleeping. */ 82 #define LO_UPGRADABLE 0x00200000 /* Lock may be upgraded/downgraded. */ 83 #define LO_DUPOK 0x00400000 /* Don't check for duplicate acquires */ 84 #define LO_IS_VNODE 0x00800000 /* Tell WITNESS about a VNODE lock */ 85 #define LO_CLASSMASK 0x0f000000 /* Class index bitmask. */ 86 #define LO_NOPROFILE 0x10000000 /* Don't profile this lock */ 87 #define LO_NEW 0x20000000 /* Don't check for double-init */ 88 89 /* 90 * Lock classes are statically assigned an index into the gobal lock_classes 91 * array. Debugging code looks up the lock class for a given lock object 92 * by indexing the array. 93 */ 94 #define LO_CLASSSHIFT 24 95 #define LO_CLASSINDEX(lock) ((((lock)->lo_flags) & LO_CLASSMASK) >> LO_CLASSSHIFT) 96 #define LOCK_CLASS(lock) (lock_classes[LO_CLASSINDEX((lock))]) 97 #define LOCK_CLASS_MAX (LO_CLASSMASK >> LO_CLASSSHIFT) 98 99 /* 100 * Option flags passed to lock operations that witness also needs to know 101 * about or that are generic across all locks. 102 */ 103 #define LOP_NEWORDER 0x00000001 /* Define a new lock order. */ 104 #define LOP_QUIET 0x00000002 /* Don't log locking operations. */ 105 #define LOP_TRYLOCK 0x00000004 /* Don't check lock order. */ 106 #define LOP_EXCLUSIVE 0x00000008 /* Exclusive lock. */ 107 #define LOP_DUPOK 0x00000010 /* Don't check for duplicate acquires */ 108 109 /* Flags passed to witness_assert. */ 110 #define LA_MASKASSERT 0x000000ff /* Mask for witness defined asserts. */ 111 #define LA_UNLOCKED 0x00000000 /* Lock is unlocked. */ 112 #define LA_LOCKED 0x00000001 /* Lock is at least share locked. */ 113 #define LA_SLOCKED 0x00000002 /* Lock is exactly share locked. */ 114 #define LA_XLOCKED 0x00000004 /* Lock is exclusively locked. */ 115 #define LA_RECURSED 0x00000008 /* Lock is recursed. */ 116 #define LA_NOTRECURSED 0x00000010 /* Lock is not recursed. */ 117 118 #ifdef _KERNEL 119 /* 120 * If any of WITNESS, INVARIANTS, or KTR_LOCK KTR tracing has been enabled, 121 * then turn on LOCK_DEBUG. When this option is on, extra debugging 122 * facilities such as tracking the file and line number of lock operations 123 * are enabled. Also, mutex locking operations are not inlined to avoid 124 * bloat from all the extra debugging code. We also have to turn on all the 125 * calling conventions for this debugging code in modules so that modules can 126 * work with both debug and non-debug kernels. 127 */ 128 #if defined(KLD_MODULE) || defined(WITNESS) || defined(INVARIANTS) || \ 129 defined(INVARIANT_SUPPORT) || defined(LOCK_PROFILING) || defined(KTR) 130 #define LOCK_DEBUG 1 131 #else 132 #define LOCK_DEBUG 0 133 #endif 134 135 /* 136 * In the LOCK_DEBUG case, use the filename and line numbers for debugging 137 * operations. Otherwise, use default values to avoid the unneeded bloat. 138 */ 139 #if LOCK_DEBUG > 0 140 #define LOCK_FILE __FILE__ 141 #define LOCK_LINE __LINE__ 142 #else 143 #define LOCK_FILE NULL 144 #define LOCK_LINE 0 145 #endif 146 147 /* 148 * Macros for KTR_LOCK tracing. 149 * 150 * opname - name of this operation (LOCK/UNLOCK/SLOCK, etc.) 151 * lo - struct lock_object * for this lock 152 * flags - flags passed to the lock operation 153 * recurse - this locks recursion level (or 0 if class is not recursable) 154 * result - result of a try lock operation 155 * file - file name 156 * line - line number 157 */ 158 #if LOCK_DEBUG > 0 159 #define LOCK_LOG_TEST(lo, flags) \ 160 (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0) 161 #else 162 #define LOCK_LOG_TEST(lo, flags) 0 163 #endif 164 165 166 #define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do { \ 167 if (LOCK_LOG_TEST((lo), (flags))) \ 168 CTR6(KTR_LOCK, opname " (%s) %s %p r = %d at %s:%d", \ 169 LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ 170 (lo), (u_int)(recurse), (file), (line)); \ 171 } while (0) 172 173 #define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do { \ 174 if (LOCK_LOG_TEST((lo), (flags))) \ 175 CTR6(KTR_LOCK, "TRY_" opname " (%s) %s %p result=%d at %s:%d",\ 176 LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ 177 (lo), (u_int)(result), (file), (line)); \ 178 } while (0) 179 180 #define LOCK_LOG_INIT(lo, flags) do { \ 181 if (LOCK_LOG_TEST((lo), (flags))) \ 182 CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo), \ 183 LOCK_CLASS(lo)->lc_name, (lo)->lo_name); \ 184 } while (0) 185 186 #define LOCK_LOG_DESTROY(lo, flags) LOCK_LOG_INIT(lo, flags) 187 188 #define lock_initialized(lo) ((lo)->lo_flags & LO_INITIALIZED) 189 190 /* 191 * Helpful macros for quickly coming up with assertions with informative 192 * panic messages. 193 */ 194 #define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) 195 #define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) 196 #define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) 197 #define MPASS4(ex, what, file, line) \ 198 KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) 199 200 extern struct lock_class lock_class_mtx_sleep; 201 extern struct lock_class lock_class_mtx_spin; 202 extern struct lock_class lock_class_sx; 203 extern struct lock_class lock_class_rw; 204 extern struct lock_class lock_class_rm; 205 extern struct lock_class lock_class_rm_sleepable; 206 extern struct lock_class lock_class_lockmgr; 207 208 extern struct lock_class *lock_classes[]; 209 210 struct lock_delay_config { 211 u_int base; 212 u_int max; 213 }; 214 215 struct lock_delay_arg { 216 struct lock_delay_config *config; 217 u_int delay; 218 u_int spin_cnt; 219 }; 220 221 static inline void 222 lock_delay_arg_init(struct lock_delay_arg *la, struct lock_delay_config *lc) 223 { 224 la->config = lc; 225 la->delay = lc->base; 226 la->spin_cnt = 0; 227 } 228 229 #define LOCK_DELAY_SYSINIT(func) \ 230 SYSINIT(func##_ld, SI_SUB_LOCK, SI_ORDER_ANY, func, NULL) 231 232 #define LOCK_DELAY_SYSINIT_DEFAULT(lc) \ 233 SYSINIT(lock_delay_##lc##_ld, SI_SUB_LOCK, SI_ORDER_ANY, \ 234 lock_delay_default_init, &lc) 235 236 void lock_init(struct lock_object *, struct lock_class *, 237 const char *, const char *, int); 238 void lock_destroy(struct lock_object *); 239 void lock_delay(struct lock_delay_arg *); 240 void lock_delay_default_init(struct lock_delay_config *); 241 void spinlock_enter(void); 242 void spinlock_exit(void); 243 void witness_init(struct lock_object *, const char *); 244 void witness_destroy(struct lock_object *); 245 int witness_defineorder(struct lock_object *, struct lock_object *); 246 void witness_checkorder(struct lock_object *, int, const char *, int, 247 struct lock_object *); 248 void witness_lock(struct lock_object *, int, const char *, int); 249 void witness_upgrade(struct lock_object *, int, const char *, int); 250 void witness_downgrade(struct lock_object *, int, const char *, int); 251 void witness_unlock(struct lock_object *, int, const char *, int); 252 void witness_save(struct lock_object *, const char **, int *); 253 void witness_restore(struct lock_object *, const char *, int); 254 int witness_list_locks(struct lock_list_entry **, 255 int (*)(const char *, ...)); 256 int witness_warn(int, struct lock_object *, const char *, ...); 257 void witness_assert(const struct lock_object *, int, const char *, int); 258 void witness_display_spinlock(struct lock_object *, struct thread *, 259 int (*)(const char *, ...)); 260 int witness_line(struct lock_object *); 261 void witness_norelease(struct lock_object *); 262 void witness_releaseok(struct lock_object *); 263 const char *witness_file(struct lock_object *); 264 void witness_thread_exit(struct thread *); 265 266 #ifdef WITNESS 267 268 /* Flags for witness_warn(). */ 269 #define WARN_GIANTOK 0x01 /* Giant is exempt from this check. */ 270 #define WARN_PANIC 0x02 /* Panic if check fails. */ 271 #define WARN_SLEEPOK 0x04 /* Sleepable locks are exempt from check. */ 272 273 #define WITNESS_INIT(lock, type) \ 274 witness_init((lock), (type)) 275 276 #define WITNESS_DESTROY(lock) \ 277 witness_destroy(lock) 278 279 #define WITNESS_CHECKORDER(lock, flags, file, line, interlock) \ 280 witness_checkorder((lock), (flags), (file), (line), (interlock)) 281 282 #define WITNESS_DEFINEORDER(lock1, lock2) \ 283 witness_defineorder((struct lock_object *)(lock1), \ 284 (struct lock_object *)(lock2)) 285 286 #define WITNESS_LOCK(lock, flags, file, line) \ 287 witness_lock((lock), (flags), (file), (line)) 288 289 #define WITNESS_UPGRADE(lock, flags, file, line) \ 290 witness_upgrade((lock), (flags), (file), (line)) 291 292 #define WITNESS_DOWNGRADE(lock, flags, file, line) \ 293 witness_downgrade((lock), (flags), (file), (line)) 294 295 #define WITNESS_UNLOCK(lock, flags, file, line) \ 296 witness_unlock((lock), (flags), (file), (line)) 297 298 #define WITNESS_CHECK(flags, lock, fmt, ...) \ 299 witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) 300 301 #define WITNESS_WARN(flags, lock, fmt, ...) \ 302 witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) 303 304 #define WITNESS_SAVE_DECL(n) \ 305 const char * __CONCAT(n, __wf); \ 306 int __CONCAT(n, __wl) 307 308 #define WITNESS_SAVE(lock, n) \ 309 witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl)) 310 311 #define WITNESS_RESTORE(lock, n) \ 312 witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl)) 313 314 #define WITNESS_NORELEASE(lock) \ 315 witness_norelease(&(lock)->lock_object) 316 317 #define WITNESS_RELEASEOK(lock) \ 318 witness_releaseok(&(lock)->lock_object) 319 320 #define WITNESS_FILE(lock) \ 321 witness_file(lock) 322 323 #define WITNESS_LINE(lock) \ 324 witness_line(lock) 325 326 #else /* WITNESS */ 327 #define WITNESS_INIT(lock, type) (void)0 328 #define WITNESS_DESTROY(lock) (void)0 329 #define WITNESS_DEFINEORDER(lock1, lock2) 0 330 #define WITNESS_CHECKORDER(lock, flags, file, line, interlock) (void)0 331 #define WITNESS_LOCK(lock, flags, file, line) (void)0 332 #define WITNESS_UPGRADE(lock, flags, file, line) (void)0 333 #define WITNESS_DOWNGRADE(lock, flags, file, line) (void)0 334 #define WITNESS_UNLOCK(lock, flags, file, line) (void)0 335 #define WITNESS_CHECK(flags, lock, fmt, ...) 0 336 #define WITNESS_WARN(flags, lock, fmt, ...) (void)0 337 #define WITNESS_SAVE_DECL(n) (void)0 338 #define WITNESS_SAVE(lock, n) (void)0 339 #define WITNESS_RESTORE(lock, n) (void)0 340 #define WITNESS_NORELEASE(lock) (void)0 341 #define WITNESS_RELEASEOK(lock) (void)0 342 #define WITNESS_FILE(lock) ("?") 343 #define WITNESS_LINE(lock) (0) 344 #endif /* WITNESS */ 345 346 #endif /* _KERNEL */ 347 #endif /* _SYS_LOCK_H_ */ 348