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: releng/11.0/sys/sys/lock.h 303953 2016-08-11 09:28:49Z mjg $ 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 39struct lock_list_entry; 40struct 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 59struct 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) || defined(INVARIANT_SUPPORT) || defined(LOCK_PROFILING) || (defined(KTR) && (KTR_COMPILE & KTR_LOCK)) 129#define LOCK_DEBUG 1 130#else 131#define LOCK_DEBUG 0 132#endif 133 134/* 135 * In the LOCK_DEBUG case, use the filename and line numbers for debugging 136 * operations. Otherwise, use default values to avoid the unneeded bloat. 137 */ 138#if LOCK_DEBUG > 0 139#define LOCK_FILE __FILE__ 140#define LOCK_LINE __LINE__ 141#else 142#define LOCK_FILE NULL 143#define LOCK_LINE 0 144#endif 145 146/* 147 * Macros for KTR_LOCK tracing. 148 * 149 * opname - name of this operation (LOCK/UNLOCK/SLOCK, etc.) 150 * lo - struct lock_object * for this lock 151 * flags - flags passed to the lock operation 152 * recurse - this locks recursion level (or 0 if class is not recursable) 153 * result - result of a try lock operation 154 * file - file name 155 * line - line number 156 */ 157#define LOCK_LOG_TEST(lo, flags) \ 158 (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0) 159 160#define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do { \ 161 if (LOCK_LOG_TEST((lo), (flags))) \ 162 CTR6(KTR_LOCK, opname " (%s) %s %p r = %d at %s:%d", \ 163 LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ 164 (lo), (u_int)(recurse), (file), (line)); \ 165} while (0) 166 167#define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do { \ 168 if (LOCK_LOG_TEST((lo), (flags))) \ 169 CTR6(KTR_LOCK, "TRY_" opname " (%s) %s %p result=%d at %s:%d",\ 170 LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ 171 (lo), (u_int)(result), (file), (line)); \ 172} while (0) 173 174#define LOCK_LOG_INIT(lo, flags) do { \ 175 if (LOCK_LOG_TEST((lo), (flags))) \ 176 CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo), \ 177 LOCK_CLASS(lo)->lc_name, (lo)->lo_name); \ 178} while (0) 179 180#define LOCK_LOG_DESTROY(lo, flags) LOCK_LOG_INIT(lo, flags) 181 182#define lock_initialized(lo) ((lo)->lo_flags & LO_INITIALIZED) 183 184/* 185 * Helpful macros for quickly coming up with assertions with informative 186 * panic messages. 187 */ 188#define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) 189#define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) 190#define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) 191#define MPASS4(ex, what, file, line) \ 192 KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) 193 194extern struct lock_class lock_class_mtx_sleep; 195extern struct lock_class lock_class_mtx_spin; 196extern struct lock_class lock_class_sx; 197extern struct lock_class lock_class_rw; 198extern struct lock_class lock_class_rm; 199extern struct lock_class lock_class_rm_sleepable; 200extern struct lock_class lock_class_lockmgr; 201 202extern struct lock_class *lock_classes[]; 203 204struct lock_delay_config { 205 u_int initial; 206 u_int step; 207 u_int min; 208 u_int max; 209}; 210 211struct lock_delay_arg { 212 struct lock_delay_config *config; 213 u_int delay; 214 u_int spin_cnt; 215}; 216 217static inline void 218lock_delay_arg_init(struct lock_delay_arg *la, struct lock_delay_config *lc) { 219 la->config = lc; 220 la->delay = 0; 221 la->spin_cnt = 0; 222} 223 224#define LOCK_DELAY_SYSINIT(func) \ 225 SYSINIT(func##_ld, SI_SUB_LOCK, SI_ORDER_ANY, func, NULL) 226 227void lock_init(struct lock_object *, struct lock_class *, 228 const char *, const char *, int); 229void lock_destroy(struct lock_object *); 230void lock_delay(struct lock_delay_arg *); 231void spinlock_enter(void); 232void spinlock_exit(void); 233void witness_init(struct lock_object *, const char *); 234void witness_destroy(struct lock_object *); 235int witness_defineorder(struct lock_object *, struct lock_object *); 236void witness_checkorder(struct lock_object *, int, const char *, int, 237 struct lock_object *); 238void witness_lock(struct lock_object *, int, const char *, int); 239void witness_upgrade(struct lock_object *, int, const char *, int); 240void witness_downgrade(struct lock_object *, int, const char *, int); 241void witness_unlock(struct lock_object *, int, const char *, int); 242void witness_save(struct lock_object *, const char **, int *); 243void witness_restore(struct lock_object *, const char *, int); 244int witness_list_locks(struct lock_list_entry **, 245 int (*)(const char *, ...)); 246int witness_warn(int, struct lock_object *, const char *, ...); 247void witness_assert(const struct lock_object *, int, const char *, int); 248void witness_display_spinlock(struct lock_object *, struct thread *, 249 int (*)(const char *, ...)); 250int witness_line(struct lock_object *); 251void witness_norelease(struct lock_object *); 252void witness_releaseok(struct lock_object *); 253const char *witness_file(struct lock_object *); 254void witness_thread_exit(struct thread *); 255 256#ifdef WITNESS 257 258/* Flags for witness_warn(). */ 259#define WARN_GIANTOK 0x01 /* Giant is exempt from this check. */ 260#define WARN_PANIC 0x02 /* Panic if check fails. */ 261#define WARN_SLEEPOK 0x04 /* Sleepable locks are exempt from check. */ 262 263#define WITNESS_INIT(lock, type) \ 264 witness_init((lock), (type)) 265 266#define WITNESS_DESTROY(lock) \ 267 witness_destroy(lock) 268 269#define WITNESS_CHECKORDER(lock, flags, file, line, interlock) \ 270 witness_checkorder((lock), (flags), (file), (line), (interlock)) 271 272#define WITNESS_DEFINEORDER(lock1, lock2) \ 273 witness_defineorder((struct lock_object *)(lock1), \ 274 (struct lock_object *)(lock2)) 275 276#define WITNESS_LOCK(lock, flags, file, line) \ 277 witness_lock((lock), (flags), (file), (line)) 278 279#define WITNESS_UPGRADE(lock, flags, file, line) \ 280 witness_upgrade((lock), (flags), (file), (line)) 281 282#define WITNESS_DOWNGRADE(lock, flags, file, line) \ 283 witness_downgrade((lock), (flags), (file), (line)) 284 285#define WITNESS_UNLOCK(lock, flags, file, line) \ 286 witness_unlock((lock), (flags), (file), (line)) 287 288#define WITNESS_CHECK(flags, lock, fmt, ...) \ 289 witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) 290 291#define WITNESS_WARN(flags, lock, fmt, ...) \ 292 witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) 293 294#define WITNESS_SAVE_DECL(n) \ 295 const char * __CONCAT(n, __wf); \ 296 int __CONCAT(n, __wl) 297 298#define WITNESS_SAVE(lock, n) \ 299 witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl)) 300 301#define WITNESS_RESTORE(lock, n) \ 302 witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl)) 303 304#define WITNESS_NORELEASE(lock) \ 305 witness_norelease(&(lock)->lock_object) 306 307#define WITNESS_RELEASEOK(lock) \ 308 witness_releaseok(&(lock)->lock_object) 309 310#define WITNESS_FILE(lock) \ 311 witness_file(lock) 312 313#define WITNESS_LINE(lock) \ 314 witness_line(lock) 315 316#else /* WITNESS */ 317#define WITNESS_INIT(lock, type) (void)0 318#define WITNESS_DESTROY(lock) (void)0 319#define WITNESS_DEFINEORDER(lock1, lock2) 0 320#define WITNESS_CHECKORDER(lock, flags, file, line, interlock) (void)0 321#define WITNESS_LOCK(lock, flags, file, line) (void)0 322#define WITNESS_UPGRADE(lock, flags, file, line) (void)0 323#define WITNESS_DOWNGRADE(lock, flags, file, line) (void)0 324#define WITNESS_UNLOCK(lock, flags, file, line) (void)0 325#define WITNESS_CHECK(flags, lock, fmt, ...) 0 326#define WITNESS_WARN(flags, lock, fmt, ...) (void)0 327#define WITNESS_SAVE_DECL(n) (void)0 328#define WITNESS_SAVE(lock, n) (void)0 329#define WITNESS_RESTORE(lock, n) (void)0 330#define WITNESS_NORELEASE(lock) (void)0 331#define WITNESS_RELEASEOK(lock) (void)0 332#define WITNESS_FILE(lock) ("?") 333#define WITNESS_LINE(lock) (0) 334#endif /* WITNESS */ 335 336#endif /* _KERNEL */ 337#endif /* _SYS_LOCK_H_ */ 338