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 Exp $ 29 * $FreeBSD$ 30 */ 31 32 #ifndef _SYS_MUTEX_H_ 33 #define _SYS_MUTEX_H_ 34 35 #include <sys/queue.h> 36 #include <sys/_lock.h> 37 #include <sys/_mutex.h> 38 39 #ifdef _KERNEL 40 #include <sys/pcpu.h> 41 #include <sys/lock_profile.h> 42 #include <sys/lockstat.h> 43 #include <machine/atomic.h> 44 #include <machine/cpufunc.h> 45 46 /* 47 * Mutex types and options passed to mtx_init(). MTX_QUIET and MTX_DUPOK 48 * can also be passed in. 49 */ 50 #define MTX_DEF 0x00000000 /* DEFAULT (sleep) lock */ 51 #define MTX_SPIN 0x00000001 /* Spin lock (disables interrupts) */ 52 #define MTX_RECURSE 0x00000004 /* Option: lock allowed to recurse */ 53 #define MTX_NOWITNESS 0x00000008 /* Don't do any witness checking. */ 54 #define MTX_NOPROFILE 0x00000020 /* Don't profile this lock */ 55 #define MTX_NEW 0x00000040 /* Don't check for double-init */ 56 57 /* 58 * Option flags passed to certain lock/unlock routines, through the use 59 * of corresponding mtx_{lock,unlock}_flags() interface macros. 60 */ 61 #define MTX_QUIET LOP_QUIET /* Don't log a mutex event */ 62 #define MTX_DUPOK LOP_DUPOK /* Don't log a duplicate acquire */ 63 64 /* 65 * State bits kept in mutex->mtx_lock, for the DEFAULT lock type. None of this, 66 * with the exception of MTX_UNOWNED, applies to spin locks. 67 */ 68 #define MTX_UNOWNED 0x00000000 /* Cookie for free mutex */ 69 #define MTX_RECURSED 0x00000001 /* lock recursed (for MTX_DEF only) */ 70 #define MTX_CONTESTED 0x00000002 /* lock contested (for MTX_DEF only) */ 71 #define MTX_DESTROYED 0x00000004 /* lock destroyed */ 72 #define MTX_FLAGMASK (MTX_RECURSED | MTX_CONTESTED | MTX_DESTROYED) 73 74 /* 75 * Prototypes 76 * 77 * NOTE: Functions prepended with `_' (underscore) are exported to other parts 78 * of the kernel via macros, thus allowing us to use the cpp LOCK_FILE 79 * and LOCK_LINE or for hiding the lock cookie crunching to the 80 * consumers. These functions should not be called directly by any 81 * code using the API. Their macros cover their functionality. 82 * Functions with a `_' suffix are the entrypoint for the common 83 * KPI covering both compat shims and fast path case. These can be 84 * used by consumers willing to pass options, file and line 85 * informations, in an option-independent way. 86 * 87 * [See below for descriptions] 88 * 89 */ 90 void _mtx_init(volatile uintptr_t *c, const char *name, const char *type, 91 int opts); 92 void _mtx_destroy(volatile uintptr_t *c); 93 void mtx_sysinit(void *arg); 94 int _mtx_trylock_flags_int(struct mtx *m, int opts LOCK_FILE_LINE_ARG_DEF); 95 int _mtx_trylock_flags_(volatile uintptr_t *c, int opts, const char *file, 96 int line); 97 void mutex_init(void); 98 #if LOCK_DEBUG > 0 99 void __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v, int opts, 100 const char *file, int line); 101 void __mtx_unlock_sleep(volatile uintptr_t *c, uintptr_t v, int opts, 102 const char *file, int line); 103 #else 104 void __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v); 105 void __mtx_unlock_sleep(volatile uintptr_t *c, uintptr_t v); 106 #endif 107 108 #ifdef SMP 109 #if LOCK_DEBUG > 0 110 void _mtx_lock_spin_cookie(volatile uintptr_t *c, uintptr_t v, int opts, 111 const char *file, int line); 112 #else 113 void _mtx_lock_spin_cookie(volatile uintptr_t *c, uintptr_t v); 114 #endif 115 #endif 116 void __mtx_lock_flags(volatile uintptr_t *c, int opts, const char *file, 117 int line); 118 void __mtx_unlock_flags(volatile uintptr_t *c, int opts, const char *file, 119 int line); 120 void __mtx_lock_spin_flags(volatile uintptr_t *c, int opts, const char *file, 121 int line); 122 int __mtx_trylock_spin_flags(volatile uintptr_t *c, int opts, 123 const char *file, int line); 124 void __mtx_unlock_spin_flags(volatile uintptr_t *c, int opts, 125 const char *file, int line); 126 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 127 void __mtx_assert(const volatile uintptr_t *c, int what, const char *file, 128 int line); 129 #endif 130 void thread_lock_flags_(struct thread *, int, const char *, int); 131 #if LOCK_DEBUG > 0 132 void _thread_lock(struct thread *td, int opts, const char *file, int line); 133 #else 134 void _thread_lock(struct thread *); 135 #endif 136 137 #if defined(LOCK_PROFILING) || defined(KLD_MODULE) 138 #define thread_lock(tdp) \ 139 thread_lock_flags_((tdp), 0, __FILE__, __LINE__) 140 #elif LOCK_DEBUG > 0 141 #define thread_lock(tdp) \ 142 _thread_lock((tdp), 0, __FILE__, __LINE__) 143 #else 144 #define thread_lock(tdp) \ 145 _thread_lock((tdp)) 146 #endif 147 148 #if LOCK_DEBUG > 0 149 #define thread_lock_flags(tdp, opt) \ 150 thread_lock_flags_((tdp), (opt), __FILE__, __LINE__) 151 #else 152 #define thread_lock_flags(tdp, opt) \ 153 _thread_lock(tdp) 154 #endif 155 156 #define thread_unlock(tdp) \ 157 mtx_unlock_spin((tdp)->td_lock) 158 159 /* 160 * Top-level macros to provide lock cookie once the actual mtx is passed. 161 * They will also prevent passing a malformed object to the mtx KPI by 162 * failing compilation as the mtx_lock reserved member will not be found. 163 */ 164 #define mtx_init(m, n, t, o) \ 165 _mtx_init(&(m)->mtx_lock, n, t, o) 166 #define mtx_destroy(m) \ 167 _mtx_destroy(&(m)->mtx_lock) 168 #define mtx_trylock_flags_(m, o, f, l) \ 169 _mtx_trylock_flags_(&(m)->mtx_lock, o, f, l) 170 #if LOCK_DEBUG > 0 171 #define _mtx_lock_sleep(m, v, o, f, l) \ 172 __mtx_lock_sleep(&(m)->mtx_lock, v, o, f, l) 173 #define _mtx_unlock_sleep(m, v, o, f, l) \ 174 __mtx_unlock_sleep(&(m)->mtx_lock, v, o, f, l) 175 #else 176 #define _mtx_lock_sleep(m, v, o, f, l) \ 177 __mtx_lock_sleep(&(m)->mtx_lock, v) 178 #define _mtx_unlock_sleep(m, v, o, f, l) \ 179 __mtx_unlock_sleep(&(m)->mtx_lock, v) 180 #endif 181 #ifdef SMP 182 #if LOCK_DEBUG > 0 183 #define _mtx_lock_spin(m, v, o, f, l) \ 184 _mtx_lock_spin_cookie(&(m)->mtx_lock, v, o, f, l) 185 #else 186 #define _mtx_lock_spin(m, v, o, f, l) \ 187 _mtx_lock_spin_cookie(&(m)->mtx_lock, v) 188 #endif 189 #endif 190 #define _mtx_lock_flags(m, o, f, l) \ 191 __mtx_lock_flags(&(m)->mtx_lock, o, f, l) 192 #define _mtx_unlock_flags(m, o, f, l) \ 193 __mtx_unlock_flags(&(m)->mtx_lock, o, f, l) 194 #define _mtx_lock_spin_flags(m, o, f, l) \ 195 __mtx_lock_spin_flags(&(m)->mtx_lock, o, f, l) 196 #define _mtx_trylock_spin_flags(m, o, f, l) \ 197 __mtx_trylock_spin_flags(&(m)->mtx_lock, o, f, l) 198 #define _mtx_unlock_spin_flags(m, o, f, l) \ 199 __mtx_unlock_spin_flags(&(m)->mtx_lock, o, f, l) 200 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 201 #define _mtx_assert(m, w, f, l) \ 202 __mtx_assert(&(m)->mtx_lock, w, f, l) 203 #endif 204 205 #define mtx_recurse lock_object.lo_data 206 207 /* Very simple operations on mtx_lock. */ 208 209 /* Try to obtain mtx_lock once. */ 210 #define _mtx_obtain_lock(mp, tid) \ 211 atomic_cmpset_acq_ptr(&(mp)->mtx_lock, MTX_UNOWNED, (tid)) 212 213 #define _mtx_obtain_lock_fetch(mp, vp, tid) \ 214 atomic_fcmpset_acq_ptr(&(mp)->mtx_lock, vp, (tid)) 215 216 /* Try to release mtx_lock if it is unrecursed and uncontested. */ 217 #define _mtx_release_lock(mp, tid) \ 218 atomic_cmpset_rel_ptr(&(mp)->mtx_lock, (tid), MTX_UNOWNED) 219 220 /* Release mtx_lock quickly, assuming we own it. */ 221 #define _mtx_release_lock_quick(mp) \ 222 atomic_store_rel_ptr(&(mp)->mtx_lock, MTX_UNOWNED) 223 224 #define _mtx_release_lock_fetch(mp, vp) \ 225 atomic_fcmpset_rel_ptr(&(mp)->mtx_lock, (vp), MTX_UNOWNED) 226 227 /* 228 * Full lock operations that are suitable to be inlined in non-debug 229 * kernels. If the lock cannot be acquired or released trivially then 230 * the work is deferred to another function. 231 */ 232 233 /* Lock a normal mutex. */ 234 #define __mtx_lock(mp, tid, opts, file, line) do { \ 235 uintptr_t _tid = (uintptr_t)(tid); \ 236 uintptr_t _v = MTX_UNOWNED; \ 237 \ 238 if (__predict_false(LOCKSTAT_PROFILE_ENABLED(adaptive__acquire) ||\ 239 !_mtx_obtain_lock_fetch((mp), &_v, _tid))) \ 240 _mtx_lock_sleep((mp), _v, (opts), (file), (line)); \ 241 } while (0) 242 243 /* 244 * Lock a spin mutex. For spinlocks, we handle recursion inline (it 245 * turns out that function calls can be significantly expensive on 246 * some architectures). Since spin locks are not _too_ common, 247 * inlining this code is not too big a deal. 248 */ 249 #ifdef SMP 250 #define __mtx_lock_spin(mp, tid, opts, file, line) do { \ 251 uintptr_t _tid = (uintptr_t)(tid); \ 252 uintptr_t _v = MTX_UNOWNED; \ 253 \ 254 spinlock_enter(); \ 255 if (__predict_false(LOCKSTAT_PROFILE_ENABLED(spin__acquire) || \ 256 !_mtx_obtain_lock_fetch((mp), &_v, _tid))) \ 257 _mtx_lock_spin((mp), _v, (opts), (file), (line)); \ 258 } while (0) 259 #define __mtx_trylock_spin(mp, tid, opts, file, line) __extension__ ({ \ 260 uintptr_t _tid = (uintptr_t)(tid); \ 261 int _ret; \ 262 \ 263 spinlock_enter(); \ 264 if (((mp)->mtx_lock != MTX_UNOWNED || !_mtx_obtain_lock((mp), _tid))) {\ 265 spinlock_exit(); \ 266 _ret = 0; \ 267 } else { \ 268 LOCKSTAT_PROFILE_OBTAIN_LOCK_SUCCESS(spin__acquire, \ 269 mp, 0, 0, file, line); \ 270 _ret = 1; \ 271 } \ 272 _ret; \ 273 }) 274 #else /* SMP */ 275 #define __mtx_lock_spin(mp, tid, opts, file, line) do { \ 276 uintptr_t _tid = (uintptr_t)(tid); \ 277 \ 278 spinlock_enter(); \ 279 if ((mp)->mtx_lock == _tid) \ 280 (mp)->mtx_recurse++; \ 281 else { \ 282 KASSERT((mp)->mtx_lock == MTX_UNOWNED, ("corrupt spinlock")); \ 283 (mp)->mtx_lock = _tid; \ 284 } \ 285 } while (0) 286 #define __mtx_trylock_spin(mp, tid, opts, file, line) __extension__ ({ \ 287 uintptr_t _tid = (uintptr_t)(tid); \ 288 int _ret; \ 289 \ 290 spinlock_enter(); \ 291 if ((mp)->mtx_lock != MTX_UNOWNED) { \ 292 spinlock_exit(); \ 293 _ret = 0; \ 294 } else { \ 295 (mp)->mtx_lock = _tid; \ 296 _ret = 1; \ 297 } \ 298 _ret; \ 299 }) 300 #endif /* SMP */ 301 302 /* Unlock a normal mutex. */ 303 #define __mtx_unlock(mp, tid, opts, file, line) do { \ 304 uintptr_t _v = (uintptr_t)(tid); \ 305 \ 306 if (__predict_false(LOCKSTAT_PROFILE_ENABLED(adaptive__release) ||\ 307 !_mtx_release_lock_fetch((mp), &_v))) \ 308 _mtx_unlock_sleep((mp), _v, (opts), (file), (line)); \ 309 } while (0) 310 311 /* 312 * Unlock a spin mutex. For spinlocks, we can handle everything 313 * inline, as it's pretty simple and a function call would be too 314 * expensive (at least on some architectures). Since spin locks are 315 * not _too_ common, inlining this code is not too big a deal. 316 * 317 * Since we always perform a spinlock_enter() when attempting to acquire a 318 * spin lock, we need to always perform a matching spinlock_exit() when 319 * releasing a spin lock. This includes the recursion cases. 320 */ 321 #ifdef SMP 322 #define __mtx_unlock_spin(mp) do { \ 323 if (mtx_recursed((mp))) \ 324 (mp)->mtx_recurse--; \ 325 else { \ 326 LOCKSTAT_PROFILE_RELEASE_LOCK(spin__release, mp); \ 327 _mtx_release_lock_quick((mp)); \ 328 } \ 329 spinlock_exit(); \ 330 } while (0) 331 #else /* SMP */ 332 #define __mtx_unlock_spin(mp) do { \ 333 if (mtx_recursed((mp))) \ 334 (mp)->mtx_recurse--; \ 335 else { \ 336 LOCKSTAT_PROFILE_RELEASE_LOCK(spin__release, mp); \ 337 (mp)->mtx_lock = MTX_UNOWNED; \ 338 } \ 339 spinlock_exit(); \ 340 } while (0) 341 #endif /* SMP */ 342 343 /* 344 * Exported lock manipulation interface. 345 * 346 * mtx_lock(m) locks MTX_DEF mutex `m' 347 * 348 * mtx_lock_spin(m) locks MTX_SPIN mutex `m' 349 * 350 * mtx_unlock(m) unlocks MTX_DEF mutex `m' 351 * 352 * mtx_unlock_spin(m) unlocks MTX_SPIN mutex `m' 353 * 354 * mtx_lock_spin_flags(m, opts) and mtx_lock_flags(m, opts) locks mutex `m' 355 * and passes option flags `opts' to the "hard" function, if required. 356 * With these routines, it is possible to pass flags such as MTX_QUIET 357 * to the appropriate lock manipulation routines. 358 * 359 * mtx_trylock(m) attempts to acquire MTX_DEF mutex `m' but doesn't sleep if 360 * it cannot. Rather, it returns 0 on failure and non-zero on success. 361 * It does NOT handle recursion as we assume that if a caller is properly 362 * using this part of the interface, he will know that the lock in question 363 * is _not_ recursed. 364 * 365 * mtx_trylock_flags(m, opts) is used the same way as mtx_trylock() but accepts 366 * relevant option flags `opts.' 367 * 368 * mtx_trylock_spin(m) attempts to acquire MTX_SPIN mutex `m' but doesn't 369 * spin if it cannot. Rather, it returns 0 on failure and non-zero on 370 * success. It always returns failure for recursed lock attempts. 371 * 372 * mtx_initialized(m) returns non-zero if the lock `m' has been initialized. 373 * 374 * mtx_owned(m) returns non-zero if the current thread owns the lock `m' 375 * 376 * mtx_recursed(m) returns non-zero if the lock `m' is presently recursed. 377 */ 378 #define mtx_lock(m) mtx_lock_flags((m), 0) 379 #define mtx_lock_spin(m) mtx_lock_spin_flags((m), 0) 380 #define mtx_trylock(m) mtx_trylock_flags((m), 0) 381 #define mtx_trylock_spin(m) mtx_trylock_spin_flags((m), 0) 382 #define mtx_unlock(m) mtx_unlock_flags((m), 0) 383 #define mtx_unlock_spin(m) mtx_unlock_spin_flags((m), 0) 384 385 struct mtx_pool; 386 387 struct mtx_pool *mtx_pool_create(const char *mtx_name, int pool_size, int opts); 388 void mtx_pool_destroy(struct mtx_pool **poolp); 389 struct mtx *mtx_pool_find(struct mtx_pool *pool, void *ptr); 390 struct mtx *mtx_pool_alloc(struct mtx_pool *pool); 391 #define mtx_pool_lock(pool, ptr) \ 392 mtx_lock(mtx_pool_find((pool), (ptr))) 393 #define mtx_pool_lock_spin(pool, ptr) \ 394 mtx_lock_spin(mtx_pool_find((pool), (ptr))) 395 #define mtx_pool_unlock(pool, ptr) \ 396 mtx_unlock(mtx_pool_find((pool), (ptr))) 397 #define mtx_pool_unlock_spin(pool, ptr) \ 398 mtx_unlock_spin(mtx_pool_find((pool), (ptr))) 399 400 /* 401 * mtxpool_sleep is a general purpose pool of sleep mutexes. 402 */ 403 extern struct mtx_pool *mtxpool_sleep; 404 405 #ifndef LOCK_DEBUG 406 #error LOCK_DEBUG not defined, include <sys/lock.h> before <sys/mutex.h> 407 #endif 408 #if LOCK_DEBUG > 0 || defined(MUTEX_NOINLINE) 409 #define mtx_lock_flags_(m, opts, file, line) \ 410 _mtx_lock_flags((m), (opts), (file), (line)) 411 #define mtx_unlock_flags_(m, opts, file, line) \ 412 _mtx_unlock_flags((m), (opts), (file), (line)) 413 #define mtx_lock_spin_flags_(m, opts, file, line) \ 414 _mtx_lock_spin_flags((m), (opts), (file), (line)) 415 #define mtx_trylock_spin_flags_(m, opts, file, line) \ 416 _mtx_trylock_spin_flags((m), (opts), (file), (line)) 417 #define mtx_unlock_spin_flags_(m, opts, file, line) \ 418 _mtx_unlock_spin_flags((m), (opts), (file), (line)) 419 #else /* LOCK_DEBUG == 0 && !MUTEX_NOINLINE */ 420 #define mtx_lock_flags_(m, opts, file, line) \ 421 __mtx_lock((m), curthread, (opts), (file), (line)) 422 #define mtx_unlock_flags_(m, opts, file, line) \ 423 __mtx_unlock((m), curthread, (opts), (file), (line)) 424 #define mtx_lock_spin_flags_(m, opts, file, line) \ 425 __mtx_lock_spin((m), curthread, (opts), (file), (line)) 426 #define mtx_trylock_spin_flags_(m, opts, file, line) \ 427 __mtx_trylock_spin((m), curthread, (opts), (file), (line)) 428 #define mtx_unlock_spin_flags_(m, opts, file, line) \ 429 __mtx_unlock_spin((m)) 430 #endif /* LOCK_DEBUG > 0 || MUTEX_NOINLINE */ 431 432 #ifdef INVARIANTS 433 #define mtx_assert_(m, what, file, line) \ 434 _mtx_assert((m), (what), (file), (line)) 435 436 #define GIANT_REQUIRED mtx_assert_(&Giant, MA_OWNED, __FILE__, __LINE__) 437 438 #else /* INVARIANTS */ 439 #define mtx_assert_(m, what, file, line) (void)0 440 #define GIANT_REQUIRED 441 #endif /* INVARIANTS */ 442 443 #define mtx_lock_flags(m, opts) \ 444 mtx_lock_flags_((m), (opts), LOCK_FILE, LOCK_LINE) 445 #define mtx_unlock_flags(m, opts) \ 446 mtx_unlock_flags_((m), (opts), LOCK_FILE, LOCK_LINE) 447 #define mtx_lock_spin_flags(m, opts) \ 448 mtx_lock_spin_flags_((m), (opts), LOCK_FILE, LOCK_LINE) 449 #define mtx_unlock_spin_flags(m, opts) \ 450 mtx_unlock_spin_flags_((m), (opts), LOCK_FILE, LOCK_LINE) 451 #define mtx_trylock_flags(m, opts) \ 452 mtx_trylock_flags_((m), (opts), LOCK_FILE, LOCK_LINE) 453 #define mtx_trylock_spin_flags(m, opts) \ 454 mtx_trylock_spin_flags_((m), (opts), LOCK_FILE, LOCK_LINE) 455 #define mtx_assert(m, what) \ 456 mtx_assert_((m), (what), __FILE__, __LINE__) 457 458 #define mtx_sleep(chan, mtx, pri, wmesg, timo) \ 459 _sleep((chan), &(mtx)->lock_object, (pri), (wmesg), \ 460 tick_sbt * (timo), 0, C_HARDCLOCK) 461 462 #define MTX_READ_VALUE(m) ((m)->mtx_lock) 463 464 #define mtx_initialized(m) lock_initialized(&(m)->lock_object) 465 466 #define lv_mtx_owner(v) ((struct thread *)((v) & ~MTX_FLAGMASK)) 467 468 #define mtx_owner(m) lv_mtx_owner(MTX_READ_VALUE(m)) 469 470 #define mtx_owned(m) (mtx_owner(m) == curthread) 471 472 #define mtx_recursed(m) ((m)->mtx_recurse != 0) 473 474 #define mtx_name(m) ((m)->lock_object.lo_name) 475 476 /* 477 * Global locks. 478 */ 479 extern struct mtx Giant; 480 extern struct mtx blocked_lock; 481 482 /* 483 * Giant lock manipulation and clean exit macros. 484 * Used to replace return with an exit Giant and return. 485 * 486 * Note that DROP_GIANT*() needs to be paired with PICKUP_GIANT() 487 * The #ifndef is to allow lint-like tools to redefine DROP_GIANT. 488 */ 489 #ifndef DROP_GIANT 490 #define DROP_GIANT() \ 491 do { \ 492 int _giantcnt = 0; \ 493 WITNESS_SAVE_DECL(Giant); \ 494 \ 495 if (mtx_owned(&Giant)) { \ 496 WITNESS_SAVE(&Giant.lock_object, Giant); \ 497 for (_giantcnt = 0; mtx_owned(&Giant) && \ 498 !SCHEDULER_STOPPED(); _giantcnt++) \ 499 mtx_unlock(&Giant); \ 500 } 501 502 #define PICKUP_GIANT() \ 503 PARTIAL_PICKUP_GIANT(); \ 504 } while (0) 505 506 #define PARTIAL_PICKUP_GIANT() \ 507 mtx_assert(&Giant, MA_NOTOWNED); \ 508 if (_giantcnt > 0) { \ 509 while (_giantcnt--) \ 510 mtx_lock(&Giant); \ 511 WITNESS_RESTORE(&Giant.lock_object, Giant); \ 512 } 513 #endif 514 515 struct mtx_args { 516 void *ma_mtx; 517 const char *ma_desc; 518 int ma_opts; 519 }; 520 521 #define MTX_SYSINIT(name, mtx, desc, opts) \ 522 static struct mtx_args name##_args = { \ 523 (mtx), \ 524 (desc), \ 525 (opts) \ 526 }; \ 527 SYSINIT(name##_mtx_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE, \ 528 mtx_sysinit, &name##_args); \ 529 SYSUNINIT(name##_mtx_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE, \ 530 _mtx_destroy, __DEVOLATILE(void *, &(mtx)->mtx_lock)) 531 532 /* 533 * The INVARIANTS-enabled mtx_assert() functionality. 534 * 535 * The constants need to be defined for INVARIANT_SUPPORT infrastructure 536 * support as _mtx_assert() itself uses them and the latter implies that 537 * _mtx_assert() must build. 538 */ 539 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 540 #define MA_OWNED LA_XLOCKED 541 #define MA_NOTOWNED LA_UNLOCKED 542 #define MA_RECURSED LA_RECURSED 543 #define MA_NOTRECURSED LA_NOTRECURSED 544 #endif 545 546 /* 547 * Common lock type names. 548 */ 549 #define MTX_NETWORK_LOCK "network driver" 550 551 #endif /* _KERNEL */ 552 #endif /* _SYS_MUTEX_H_ */ 553