1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Berkeley Software Design Inc's name may not be used to endorse or
15 * promote products derived from this software without specific prior
16 * written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * from BSDI $Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp Exp $
31 */
32
33#ifndef _SYS_MUTEX_H_
34#define _SYS_MUTEX_H_
35
36#include <sys/queue.h>
37#include <sys/_lock.h>
38#include <sys/_mutex.h>
39
40#ifdef _KERNEL
41#include <sys/pcpu.h>
42#include <sys/lock_profile.h>
43#include <sys/lockstat.h>
44#include <machine/atomic.h>
45#include <machine/cpufunc.h>
46
47/*
48 * Mutex types and options passed to mtx_init(). MTX_QUIET and MTX_DUPOK
49 * can also be passed in.
50 */
51#define MTX_DEF 0x00000000 /* DEFAULT (sleep) lock */
52#define MTX_SPIN 0x00000001 /* Spin lock (disables interrupts) */
53#define MTX_RECURSE 0x00000004 /* Option: lock allowed to recurse */
54#define MTX_NOWITNESS 0x00000008 /* Don't do any witness checking. */
55#define MTX_NOPROFILE 0x00000020 /* Don't profile this lock */
56#define MTX_NEW 0x00000040 /* Don't check for double-init */
57
58/*
59 * Option flags passed to certain lock/unlock routines, through the use
60 * of corresponding mtx_{lock,unlock}_flags() interface macros.
61 */
62#define MTX_QUIET LOP_QUIET /* Don't log a mutex event */
63#define MTX_DUPOK LOP_DUPOK /* Don't log a duplicate acquire */
64
65/*
66 * State bits kept in mutex->mtx_lock, for the DEFAULT lock type. None of this,
67 * with the exception of MTX_UNOWNED, applies to spin locks.
68 */
69#define MTX_UNOWNED 0x00000000 /* Cookie for free mutex */
70#define MTX_RECURSED 0x00000001 /* lock recursed (for MTX_DEF only) */
71#define MTX_CONTESTED 0x00000002 /* lock contested (for MTX_DEF only) */
72#define MTX_DESTROYED 0x00000004 /* lock destroyed */
73#define MTX_FLAGMASK (MTX_RECURSED | MTX_CONTESTED | MTX_DESTROYED)
74
75/*
76 * Prototypes
77 *
78 * NOTE: Functions prepended with `_' (underscore) are exported to other parts
79 * of the kernel via macros, thus allowing us to use the cpp LOCK_FILE
80 * and LOCK_LINE or for hiding the lock cookie crunching to the
81 * consumers. These functions should not be called directly by any
82 * code using the API. Their macros cover their functionality.
83 * Functions with a `_' suffix are the entrypoint for the common
84 * KPI covering both compat shims and fast path case. These can be
85 * used by consumers willing to pass options, file and line
86 * informations, in an option-independent way.
87 *
88 * [See below for descriptions]
89 *
90 */
91void _mtx_init(volatile uintptr_t *c, const char *name, const char *type,
92 int opts);
93void _mtx_destroy(volatile uintptr_t *c);
94void mtx_sysinit(const void *arg);
95int _mtx_trylock_flags_int(struct mtx *m, int opts LOCK_FILE_LINE_ARG_DEF);
96int _mtx_trylock_flags_(volatile uintptr_t *c, int opts, const char *file,
97 int line);
98void mutex_init(void);
99#if LOCK_DEBUG > 0
100void __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v, int opts,
101 const char *file, int line);
102void __mtx_unlock_sleep(volatile uintptr_t *c, uintptr_t v, int opts,
103 const char *file, int line);
104#else
105void __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v);
106void __mtx_unlock_sleep(volatile uintptr_t *c, uintptr_t v);
107#endif
108void mtx_wait_unlocked(struct mtx *m);
109
110#ifdef SMP
111#if LOCK_DEBUG > 0
112void _mtx_lock_spin_cookie(volatile uintptr_t *c, uintptr_t v, int opts,
113 const char *file, int line);
114#else
115void _mtx_lock_spin_cookie(volatile uintptr_t *c, uintptr_t v);
116#endif
117#endif
118void __mtx_lock_flags(volatile uintptr_t *c, int opts, const char *file,
119 int line);
120void __mtx_unlock_flags(volatile uintptr_t *c, int opts, const char *file,
121 int line);
122void __mtx_lock_spin_flags(volatile uintptr_t *c, int opts, const char *file,
123 int line);
124int __mtx_trylock_spin_flags(volatile uintptr_t *c, int opts,
125 const char *file, int line);
126void __mtx_unlock_spin_flags(volatile uintptr_t *c, int opts,
127 const char *file, int line);
128void mtx_spin_wait_unlocked(struct mtx *m);
129
130#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
131void __mtx_assert(const volatile uintptr_t *c, int what, const char *file,
132 int line);
133#endif
134void thread_lock_flags_(struct thread *, int, const char *, int);
135#if LOCK_DEBUG > 0
136void _thread_lock(struct thread *td, int opts, const char *file, int line);
137#else
138void _thread_lock(struct thread *);
139#endif
140
141#if defined(LOCK_PROFILING) || (defined(KLD_MODULE) && !defined(KLD_TIED))
142#define thread_lock(tdp) \
143 thread_lock_flags_((tdp), 0, __FILE__, __LINE__)
144#elif LOCK_DEBUG > 0
145#define thread_lock(tdp) \
146 _thread_lock((tdp), 0, __FILE__, __LINE__)
147#else
148#define thread_lock(tdp) \
149 _thread_lock((tdp))
150#endif
151
152#if LOCK_DEBUG > 0
153#define thread_lock_flags(tdp, opt) \
154 thread_lock_flags_((tdp), (opt), __FILE__, __LINE__)
155#else
156#define thread_lock_flags(tdp, opt) \
157 _thread_lock(tdp)
158#endif
159
160#define thread_unlock(tdp) \
161 mtx_unlock_spin((tdp)->td_lock)
162
163/*
164 * Top-level macros to provide lock cookie once the actual mtx is passed.
165 * They will also prevent passing a malformed object to the mtx KPI by
166 * failing compilation as the mtx_lock reserved member will not be found.
167 */
168#define mtx_init(m, n, t, o) \
169 _mtx_init(&(m)->mtx_lock, n, t, o)
170#define mtx_destroy(m) \
171 _mtx_destroy(&(m)->mtx_lock)
172#define mtx_trylock_flags_(m, o, f, l) \
173 _mtx_trylock_flags_(&(m)->mtx_lock, o, f, l)
174#if LOCK_DEBUG > 0
175#define _mtx_lock_sleep(m, v, o, f, l) \
176 __mtx_lock_sleep(&(m)->mtx_lock, v, o, f, l)
177#define _mtx_unlock_sleep(m, v, o, f, l) \
178 __mtx_unlock_sleep(&(m)->mtx_lock, v, o, f, l)
179#else
180#define _mtx_lock_sleep(m, v, o, f, l) \
181 __mtx_lock_sleep(&(m)->mtx_lock, v)
182#define _mtx_unlock_sleep(m, v, o, f, l) \
183 __mtx_unlock_sleep(&(m)->mtx_lock, v)
184#endif
185#ifdef SMP
186#if LOCK_DEBUG > 0
187#define _mtx_lock_spin(m, v, o, f, l) \
188 _mtx_lock_spin_cookie(&(m)->mtx_lock, v, o, f, l)
189#else
190#define _mtx_lock_spin(m, v, o, f, l) \
191 _mtx_lock_spin_cookie(&(m)->mtx_lock, v)
192#endif
193#endif
194#define _mtx_lock_flags(m, o, f, l) \
195 __mtx_lock_flags(&(m)->mtx_lock, o, f, l)
196#define _mtx_unlock_flags(m, o, f, l) \
197 __mtx_unlock_flags(&(m)->mtx_lock, o, f, l)
198#define _mtx_lock_spin_flags(m, o, f, l) \
199 __mtx_lock_spin_flags(&(m)->mtx_lock, o, f, l)
200#define _mtx_trylock_spin_flags(m, o, f, l) \
201 __mtx_trylock_spin_flags(&(m)->mtx_lock, o, f, l)
202#define _mtx_unlock_spin_flags(m, o, f, l) \
203 __mtx_unlock_spin_flags(&(m)->mtx_lock, o, f, l)
204#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
205#define _mtx_assert(m, w, f, l) \
206 __mtx_assert(&(m)->mtx_lock, w, f, l)
207#endif
208
209#define mtx_recurse lock_object.lo_data
210
211/* Very simple operations on mtx_lock. */
212
213/* Try to obtain mtx_lock once. */
214#define _mtx_obtain_lock(mp, tid) \
215 atomic_cmpset_acq_ptr(&(mp)->mtx_lock, MTX_UNOWNED, (tid))
216
217#define _mtx_obtain_lock_fetch(mp, vp, tid) \
218 atomic_fcmpset_acq_ptr(&(mp)->mtx_lock, vp, (tid))
219
220/* Try to release mtx_lock if it is unrecursed and uncontested. */
221#define _mtx_release_lock(mp, tid) \
222 atomic_cmpset_rel_ptr(&(mp)->mtx_lock, (tid), MTX_UNOWNED)
223
224/* Release mtx_lock quickly, assuming we own it. */
225#define _mtx_release_lock_quick(mp) \
226 atomic_store_rel_ptr(&(mp)->mtx_lock, MTX_UNOWNED)
227
228#define _mtx_release_lock_fetch(mp, vp) \
229 atomic_fcmpset_rel_ptr(&(mp)->mtx_lock, (vp), MTX_UNOWNED)
230
231/*
232 * Full lock operations that are suitable to be inlined in non-debug
233 * kernels. If the lock cannot be acquired or released trivially then
234 * the work is deferred to another function.
235 */
236
237/* Lock a normal mutex. */
238#define __mtx_lock(mp, tid, opts, file, line) __extension__ ({ \
239 uintptr_t _tid = (uintptr_t)(tid); \
240 uintptr_t _v = MTX_UNOWNED; \
241 \
242 if (__predict_false(LOCKSTAT_PROFILE_ENABLED(adaptive__acquire) ||\
243 !_mtx_obtain_lock_fetch((mp), &_v, _tid))) \
244 _mtx_lock_sleep((mp), _v, (opts), (file), (line)); \
245 (void)0; /* ensure void type for expression */ \
246})
247
248/*
249 * Lock a spin mutex. For spinlocks, we handle recursion inline (it
250 * turns out that function calls can be significantly expensive on
251 * some architectures). Since spin locks are not _too_ common,
252 * inlining this code is not too big a deal.
253 */
254#ifdef SMP
255#define __mtx_lock_spin(mp, tid, opts, file, line) __extension__ ({ \
256 uintptr_t _tid = (uintptr_t)(tid); \
257 uintptr_t _v = MTX_UNOWNED; \
258 \
259 spinlock_enter(); \
260 if (__predict_false(LOCKSTAT_PROFILE_ENABLED(spin__acquire) || \
261 !_mtx_obtain_lock_fetch((mp), &_v, _tid))) \
262 _mtx_lock_spin((mp), _v, (opts), (file), (line)); \
263 (void)0; /* ensure void type for expression */ \
264})
265#define __mtx_trylock_spin(mp, tid, opts, file, line) __extension__ ({ \
266 uintptr_t _tid = (uintptr_t)(tid); \
267 int _ret; \
268 \
269 spinlock_enter(); \
270 if (((mp)->mtx_lock != MTX_UNOWNED || !_mtx_obtain_lock((mp), _tid))) {\
271 spinlock_exit(); \
272 _ret = 0; \
273 } else { \
274 LOCKSTAT_PROFILE_OBTAIN_SPIN_LOCK_SUCCESS(spin__acquire, \
275 mp, 0, 0, file, line); \
276 _ret = 1; \
277 } \
278 _ret; \
279})
280#else /* SMP */
281#define __mtx_lock_spin(mp, tid, opts, file, line) __extension__ ({ \
282 uintptr_t _tid = (uintptr_t)(tid); \
283 \
284 spinlock_enter(); \
285 if ((mp)->mtx_lock == _tid) \
286 (mp)->mtx_recurse++; \
287 else { \
288 KASSERT((mp)->mtx_lock == MTX_UNOWNED, ("corrupt spinlock")); \
289 (mp)->mtx_lock = _tid; \
290 } \
291 (void)0; /* ensure void type for expression */ \
292})
293#define __mtx_trylock_spin(mp, tid, opts, file, line) __extension__ ({ \
294 uintptr_t _tid = (uintptr_t)(tid); \
295 int _ret; \
296 \
297 spinlock_enter(); \
298 if ((mp)->mtx_lock != MTX_UNOWNED) { \
299 spinlock_exit(); \
300 _ret = 0; \
301 } else { \
302 (mp)->mtx_lock = _tid; \
303 _ret = 1; \
304 } \
305 _ret; \
306})
307#endif /* SMP */
308
309/* Unlock a normal mutex. */
310#define __mtx_unlock(mp, tid, opts, file, line) __extension__ ({ \
311 uintptr_t _v = (uintptr_t)(tid); \
312 \
313 if (__predict_false(LOCKSTAT_PROFILE_ENABLED(adaptive__release) ||\
314 !_mtx_release_lock_fetch((mp), &_v))) \
315 _mtx_unlock_sleep((mp), _v, (opts), (file), (line)); \
316 (void)0; /* ensure void type for expression */ \
317})
318
319/*
320 * Unlock a spin mutex. For spinlocks, we can handle everything
321 * inline, as it's pretty simple and a function call would be too
322 * expensive (at least on some architectures). Since spin locks are
323 * not _too_ common, inlining this code is not too big a deal.
324 *
325 * Since we always perform a spinlock_enter() when attempting to acquire a
326 * spin lock, we need to always perform a matching spinlock_exit() when
327 * releasing a spin lock. This includes the recursion cases.
328 */
329#ifdef SMP
330#define __mtx_unlock_spin(mp) __extension__ ({ \
331 if (mtx_recursed((mp))) \
332 (mp)->mtx_recurse--; \
333 else { \
334 LOCKSTAT_PROFILE_RELEASE_SPIN_LOCK(spin__release, mp); \
335 _mtx_release_lock_quick((mp)); \
336 } \
337 spinlock_exit(); \
338})
339#else /* SMP */
340#define __mtx_unlock_spin(mp) __extension__ ({ \
341 if (mtx_recursed((mp))) \
342 (mp)->mtx_recurse--; \
343 else { \
344 LOCKSTAT_PROFILE_RELEASE_SPIN_LOCK(spin__release, mp); \
345 (mp)->mtx_lock = MTX_UNOWNED; \
346 } \
347 spinlock_exit(); \
348})
349#endif /* SMP */
350
351/*
352 * Exported lock manipulation interface.
353 *
354 * mtx_lock(m) locks MTX_DEF mutex `m'
355 *
356 * mtx_lock_spin(m) locks MTX_SPIN mutex `m'
357 *
358 * mtx_unlock(m) unlocks MTX_DEF mutex `m'
359 *
360 * mtx_unlock_spin(m) unlocks MTX_SPIN mutex `m'
361 *
362 * mtx_lock_spin_flags(m, opts) and mtx_lock_flags(m, opts) locks mutex `m'
363 * and passes option flags `opts' to the "hard" function, if required.
364 * With these routines, it is possible to pass flags such as MTX_QUIET
365 * to the appropriate lock manipulation routines.
366 *
367 * mtx_trylock(m) attempts to acquire MTX_DEF mutex `m' but doesn't sleep if
368 * it cannot. Rather, it returns 0 on failure and non-zero on success.
369 * It does NOT handle recursion as we assume that if a caller is properly
370 * using this part of the interface, he will know that the lock in question
371 * is _not_ recursed.
372 *
373 * mtx_trylock_flags(m, opts) is used the same way as mtx_trylock() but accepts
374 * relevant option flags `opts.'
375 *
376 * mtx_trylock_spin(m) attempts to acquire MTX_SPIN mutex `m' but doesn't
377 * spin if it cannot. Rather, it returns 0 on failure and non-zero on
378 * success. It always returns failure for recursed lock attempts.
379 *
380 * mtx_initialized(m) returns non-zero if the lock `m' has been initialized.
381 *
382 * mtx_owned(m) returns non-zero if the current thread owns the lock `m'
383 *
384 * mtx_recursed(m) returns non-zero if the lock `m' is presently recursed.
385 */
386#define mtx_lock(m) mtx_lock_flags((m), 0)
387#define mtx_lock_spin(m) mtx_lock_spin_flags((m), 0)
388#define mtx_trylock(m) mtx_trylock_flags((m), 0)
389#define mtx_trylock_spin(m) mtx_trylock_spin_flags((m), 0)
390#define mtx_unlock(m) mtx_unlock_flags((m), 0)
391#define mtx_unlock_spin(m) mtx_unlock_spin_flags((m), 0)
392
393struct mtx_pool;
394
395struct mtx_pool *mtx_pool_create(const char *mtx_name, int pool_size, int opts);
396void mtx_pool_destroy(struct mtx_pool **poolp);
397struct mtx *mtx_pool_find(struct mtx_pool *pool, void *ptr);
398struct mtx *mtx_pool_alloc(struct mtx_pool *pool);
399#define mtx_pool_lock(pool, ptr) \
400 mtx_lock(mtx_pool_find((pool), (ptr)))
401#define mtx_pool_lock_spin(pool, ptr) \
402 mtx_lock_spin(mtx_pool_find((pool), (ptr)))
403#define mtx_pool_unlock(pool, ptr) \
404 mtx_unlock(mtx_pool_find((pool), (ptr)))
405#define mtx_pool_unlock_spin(pool, ptr) \
406 mtx_unlock_spin(mtx_pool_find((pool), (ptr)))
407
408/*
409 * mtxpool_sleep is a general purpose pool of sleep mutexes.
410 */
411extern struct mtx_pool *mtxpool_sleep;
412
413#ifndef LOCK_DEBUG
414#error LOCK_DEBUG not defined, include <sys/lock.h> before <sys/mutex.h>
415#endif
416#if LOCK_DEBUG > 0 || defined(MUTEX_NOINLINE)
417#define mtx_lock_flags_(m, opts, file, line) \
418 _mtx_lock_flags((m), (opts), (file), (line))
419#define mtx_unlock_flags_(m, opts, file, line) \
420 _mtx_unlock_flags((m), (opts), (file), (line))
421#define mtx_lock_spin_flags_(m, opts, file, line) \
422 _mtx_lock_spin_flags((m), (opts), (file), (line))
423#define mtx_trylock_spin_flags_(m, opts, file, line) \
424 _mtx_trylock_spin_flags((m), (opts), (file), (line))
425#define mtx_unlock_spin_flags_(m, opts, file, line) \
426 _mtx_unlock_spin_flags((m), (opts), (file), (line))
427#else /* LOCK_DEBUG == 0 && !MUTEX_NOINLINE */
428#define mtx_lock_flags_(m, opts, file, line) \
429 __mtx_lock((m), curthread, (opts), (file), (line))
430#define mtx_unlock_flags_(m, opts, file, line) \
431 __mtx_unlock((m), curthread, (opts), (file), (line))
432#define mtx_lock_spin_flags_(m, opts, file, line) \
433 __mtx_lock_spin((m), curthread, (opts), (file), (line))
434#define mtx_trylock_spin_flags_(m, opts, file, line) \
435 __mtx_trylock_spin((m), curthread, (opts), (file), (line))
436#define mtx_unlock_spin_flags_(m, opts, file, line) \
437 __mtx_unlock_spin((m))
438#endif /* LOCK_DEBUG > 0 || MUTEX_NOINLINE */
439
440#ifdef INVARIANTS
441#define mtx_assert_(m, what, file, line) \
442 _mtx_assert((m), (what), (file), (line))
443
444#define GIANT_REQUIRED mtx_assert_(&Giant, MA_OWNED, __FILE__, __LINE__)
445
446#else /* INVARIANTS */
447#define mtx_assert_(m, what, file, line) (void)0
448#define GIANT_REQUIRED
449#endif /* INVARIANTS */
450
451#define mtx_lock_flags(m, opts) \
452 mtx_lock_flags_((m), (opts), LOCK_FILE, LOCK_LINE)
453#define mtx_unlock_flags(m, opts) \
454 mtx_unlock_flags_((m), (opts), LOCK_FILE, LOCK_LINE)
455#define mtx_lock_spin_flags(m, opts) \
456 mtx_lock_spin_flags_((m), (opts), LOCK_FILE, LOCK_LINE)
457#define mtx_unlock_spin_flags(m, opts) \
458 mtx_unlock_spin_flags_((m), (opts), LOCK_FILE, LOCK_LINE)
459#define mtx_trylock_flags(m, opts) \
460 mtx_trylock_flags_((m), (opts), LOCK_FILE, LOCK_LINE)
461#define mtx_trylock_spin_flags(m, opts) \
462 mtx_trylock_spin_flags_((m), (opts), LOCK_FILE, LOCK_LINE)
463#define mtx_assert(m, what) \
464 mtx_assert_((m), (what), __FILE__, __LINE__)
465
466#define mtx_sleep(chan, mtx, pri, wmesg, timo) \
467 _sleep((chan), &(mtx)->lock_object, (pri), (wmesg), \
468 tick_sbt * (timo), 0, C_HARDCLOCK)
469
470#define MTX_READ_VALUE(m) ((m)->mtx_lock)
471
472#define mtx_initialized(m) lock_initialized(&(m)->lock_object)
473
474#define lv_mtx_owner(v) ((struct thread *)((v) & ~MTX_FLAGMASK))
475
476#define mtx_owner(m) lv_mtx_owner(MTX_READ_VALUE(m))
477
478#define mtx_owned(m) (mtx_owner(m) == curthread)
479
480#define mtx_recursed(m) ((m)->mtx_recurse != 0)
481
482#define mtx_name(m) ((m)->lock_object.lo_name)
483
484/*
485 * Global locks.
486 */
487extern struct mtx Giant;
488extern struct mtx blocked_lock;
489
490/*
491 * Giant lock manipulation and clean exit macros.
492 * Used to replace return with an exit Giant and return.
493 *
494 * Note that DROP_GIANT*() needs to be paired with PICKUP_GIANT()
495 * The #ifndef is to allow lint-like tools to redefine DROP_GIANT.
496 */
497#ifndef DROP_GIANT
498#define DROP_GIANT() \
499do { \
500 int _giantcnt = 0; \
501 WITNESS_SAVE_DECL(Giant); \
502 \
503 if (__predict_false(mtx_owned(&Giant))) { \
504 WITNESS_SAVE(&Giant.lock_object, Giant); \
505 for (_giantcnt = 0; mtx_owned(&Giant) && \
506 !SCHEDULER_STOPPED(); _giantcnt++) \
507 mtx_unlock(&Giant); \
508 }
509
510#define PICKUP_GIANT() \
511 mtx_assert(&Giant, MA_NOTOWNED); \
512 if (__predict_false(_giantcnt > 0)) { \
513 while (_giantcnt--) \
514 mtx_lock(&Giant); \
515 WITNESS_RESTORE(&Giant.lock_object, Giant); \
516 } \
517} while (0)
518#endif
519
520struct mtx_args {
521 void *ma_mtx;
522 const char *ma_desc;
523 int ma_opts;
524};
525
526#define MTX_SYSINIT(name, mtx, desc, opts) \
527 static struct mtx_args name##_args = { \
528 (mtx), \
529 (desc), \
530 (opts) \
531 }; \
532 SYSINIT(name##_mtx_sysinit, SI_SUB_LOCK, SI_ORDER_MIDDLE, \
533 mtx_sysinit, &name##_args); \
534 SYSUNINIT(name##_mtx_sysuninit, SI_SUB_LOCK, SI_ORDER_MIDDLE, \
535 _mtx_destroy, __DEVOLATILE(void *, &(mtx)->mtx_lock))
536
537/*
538 * The INVARIANTS-enabled mtx_assert() functionality.
539 *
540 * The constants need to be defined for INVARIANT_SUPPORT infrastructure
541 * support as _mtx_assert() itself uses them and the latter implies that
542 * _mtx_assert() must build.
543 */
544#if defined(INVARIANTS) || defined(INVARIANT_SUPPORT)
545#define MA_OWNED LA_XLOCKED
546#define MA_NOTOWNED LA_UNLOCKED
547#define MA_RECURSED LA_RECURSED
548#define MA_NOTRECURSED LA_NOTRECURSED
549#endif
550
551/*
552 * Common lock type names.
553 */
554#define MTX_NETWORK_LOCK "network driver"
555
556#endif /* _KERNEL */
557#endif /* _SYS_MUTEX_H_ */