xref: /netbsd-src/sys/kern/subr_lockdebug.c (revision 87fcbb0fe8532770f75df8542a0f343fd83ae1c4)
1 /*	$NetBSD: subr_lockdebug.c,v 1.17 2007/11/21 10:21:40 yamt Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Basic lock debugging code shared among lock primitives.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.17 2007/11/21 10:21:40 yamt Exp $");
45 
46 #include "opt_multiprocessor.h"
47 #include "opt_ddb.h"
48 
49 #include <sys/param.h>
50 #include <sys/proc.h>
51 #include <sys/systm.h>
52 #include <sys/kernel.h>
53 #include <sys/kmem.h>
54 #include <sys/lock.h>
55 #include <sys/lockdebug.h>
56 #include <sys/sleepq.h>
57 #include <sys/cpu.h>
58 
59 #include <lib/libkern/rb.h>
60 
61 #ifdef LOCKDEBUG
62 
63 #define	LD_BATCH_SHIFT	9
64 #define	LD_BATCH	(1 << LD_BATCH_SHIFT)
65 #define	LD_BATCH_MASK	(LD_BATCH - 1)
66 #define	LD_MAX_LOCKS	1048576
67 #define	LD_SLOP		16
68 
69 #define	LD_LOCKED	0x01
70 #define	LD_SLEEPER	0x02
71 
72 typedef union lockdebuglk {
73 	struct {
74 		__cpu_simple_lock_t	lku_lock;
75 		int			lku_oldspl;
76 	} ul;
77 	uint8_t	lk_pad[64];
78 } volatile __aligned(64) lockdebuglk_t;
79 
80 #define	lk_lock		ul.lku_lock
81 #define	lk_oldspl	ul.lku_oldspl
82 
83 typedef struct lockdebug {
84 	struct rb_node	ld_rb_node;	/* must be the first member */
85 	_TAILQ_ENTRY(struct lockdebug, volatile) ld_chain;
86 	_TAILQ_ENTRY(struct lockdebug, volatile) ld_achain;
87 	volatile void	*ld_lock;
88 	lockops_t	*ld_lockops;
89 	struct lwp	*ld_lwp;
90 	uintptr_t	ld_locked;
91 	uintptr_t	ld_unlocked;
92 	uintptr_t	ld_initaddr;
93 	uint16_t	ld_shares;
94 	uint16_t	ld_cpu;
95 	uint8_t		ld_flags;
96 	uint8_t		ld_shwant;	/* advisory */
97 	uint8_t		ld_exwant;	/* advisory */
98 	uint8_t		ld_unused;
99 } volatile lockdebug_t;
100 
101 typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t;
102 
103 lockdebuglk_t		ld_tree_lk;
104 lockdebuglk_t		ld_sleeper_lk;
105 lockdebuglk_t		ld_spinner_lk;
106 lockdebuglk_t		ld_free_lk;
107 
108 lockdebuglist_t		ld_sleepers = TAILQ_HEAD_INITIALIZER(ld_sleepers);
109 lockdebuglist_t		ld_spinners = TAILQ_HEAD_INITIALIZER(ld_spinners);
110 lockdebuglist_t		ld_free = TAILQ_HEAD_INITIALIZER(ld_free);
111 lockdebuglist_t		ld_all = TAILQ_HEAD_INITIALIZER(ld_all);
112 int			ld_nfree;
113 int			ld_freeptr;
114 int			ld_recurse;
115 bool			ld_nomore;
116 lockdebug_t		*ld_table[LD_MAX_LOCKS / LD_BATCH];
117 
118 lockdebug_t		ld_prime[LD_BATCH];
119 
120 static void	lockdebug_abort1(lockdebug_t *, lockdebuglk_t *lk,
121 				 const char *, const char *, bool);
122 static void	lockdebug_more(void);
123 static void	lockdebug_init(void);
124 
125 static signed int
126 ld_rb_compare_nodes(const struct rb_node *n1, const struct rb_node *n2)
127 {
128 	const lockdebug_t *ld1 = (const void *)n1;
129 	const lockdebug_t *ld2 = (const void *)n2;
130 	intptr_t diff = (intptr_t)ld1->ld_lock - (intptr_t)ld2->ld_lock;
131 	if (diff < 0)
132 		return -1;
133 	else if (diff > 0)
134 		return 1;
135 	return 0;
136 }
137 
138 static signed int
139 ld_rb_compare_key(const struct rb_node *n, const void *key)
140 {
141 	const lockdebug_t *ld = (const void *)n;
142 	intptr_t diff = (intptr_t)ld->ld_lock - (intptr_t)key;
143 	if (diff < 0)
144 		return -1;
145 	else if (diff > 0)
146 		return 1;
147 	return 0;
148 }
149 
150 static struct rb_tree ld_rb_tree;
151 
152 static const struct rb_tree_ops ld_rb_tree_ops = {
153 	.rb_compare_nodes = ld_rb_compare_nodes,
154 	.rb_compare_key = ld_rb_compare_key,
155 };
156 
157 static inline void
158 lockdebug_lock(lockdebuglk_t *lk)
159 {
160 	int s;
161 
162 	s = splhigh();
163 	__cpu_simple_lock(&lk->lk_lock);
164 	lk->lk_oldspl = s;
165 }
166 
167 static inline void
168 lockdebug_unlock(lockdebuglk_t *lk)
169 {
170 	int s;
171 
172 	s = lk->lk_oldspl;
173 	__cpu_simple_unlock(&(lk->lk_lock));
174 	splx(s);
175 }
176 
177 /*
178  * lockdebug_lookup:
179  *
180  *	Find a lockdebug structure by a pointer to a lock and return it locked.
181  */
182 static inline lockdebug_t *
183 lockdebug_lookup(volatile void *lock, lockdebuglk_t **lk)
184 {
185 	lockdebug_t *ld;
186 
187 	lockdebug_lock(&ld_tree_lk);
188 	ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock));
189 	lockdebug_unlock(&ld_tree_lk);
190 	if (ld == NULL)
191 		panic("lockdebug_lookup: uninitialized lock (lock=%p)", lock);
192 
193 	if ((ld->ld_flags & LD_SLEEPER) != 0)
194 		*lk = &ld_sleeper_lk;
195 	else
196 		*lk = &ld_spinner_lk;
197 
198 	lockdebug_lock(*lk);
199 	return ld;
200 }
201 
202 /*
203  * lockdebug_init:
204  *
205  *	Initialize the lockdebug system.  Allocate an initial pool of
206  *	lockdebug structures before the VM system is up and running.
207  */
208 static void
209 lockdebug_init(void)
210 {
211 	lockdebug_t *ld;
212 	int i;
213 
214 	__cpu_simple_lock_init(&ld_tree_lk.lk_lock);
215 	__cpu_simple_lock_init(&ld_sleeper_lk.lk_lock);
216 	__cpu_simple_lock_init(&ld_spinner_lk.lk_lock);
217 	__cpu_simple_lock_init(&ld_free_lk.lk_lock);
218 
219 	rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops);
220 
221 	ld = ld_prime;
222 	ld_table[0] = ld;
223 	for (i = 1, ld++; i < LD_BATCH; i++, ld++) {
224 		TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
225 		TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
226 	}
227 	ld_freeptr = 1;
228 	ld_nfree = LD_BATCH - 1;
229 }
230 
231 /*
232  * lockdebug_alloc:
233  *
234  *	A lock is being initialized, so allocate an associated debug
235  *	structure.
236  */
237 bool
238 lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr)
239 {
240 	struct cpu_info *ci;
241 	lockdebug_t *ld;
242 
243 	if (lo == NULL || panicstr != NULL)
244 		return false;
245 	if (ld_freeptr == 0)
246 		lockdebug_init();
247 
248 	ci = curcpu();
249 
250 	/*
251 	 * Pinch a new debug structure.  We may recurse because we call
252 	 * kmem_alloc(), which may need to initialize new locks somewhere
253 	 * down the path.  If not recursing, we try to maintain at least
254 	 * LD_SLOP structures free, which should hopefully be enough to
255 	 * satisfy kmem_alloc().  If we can't provide a structure, not to
256 	 * worry: we'll just mark the lock as not having an ID.
257 	 */
258 	lockdebug_lock(&ld_free_lk);
259 	ci->ci_lkdebug_recurse++;
260 
261 	if (TAILQ_EMPTY(&ld_free)) {
262 		if (ci->ci_lkdebug_recurse > 1 || ld_nomore) {
263 			ci->ci_lkdebug_recurse--;
264 			lockdebug_unlock(&ld_free_lk);
265 			return false;
266 		}
267 		lockdebug_more();
268 	} else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP)
269 		lockdebug_more();
270 
271 	if ((ld = TAILQ_FIRST(&ld_free)) == NULL) {
272 		lockdebug_unlock(&ld_free_lk);
273 		return false;
274 	}
275 
276 	TAILQ_REMOVE(&ld_free, ld, ld_chain);
277 	ld_nfree--;
278 
279 	ci->ci_lkdebug_recurse--;
280 	lockdebug_unlock(&ld_free_lk);
281 
282 	if (ld->ld_lock != NULL)
283 		panic("lockdebug_alloc: corrupt table");
284 
285 	if (lo->lo_sleeplock)
286 		lockdebug_lock(&ld_sleeper_lk);
287 	else
288 		lockdebug_lock(&ld_spinner_lk);
289 
290 	/* Initialise the structure. */
291 	ld->ld_lock = lock;
292 	ld->ld_lockops = lo;
293 	ld->ld_locked = 0;
294 	ld->ld_unlocked = 0;
295 	ld->ld_lwp = NULL;
296 	ld->ld_initaddr = initaddr;
297 
298 	lockdebug_lock(&ld_tree_lk);
299 	rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
300 	lockdebug_unlock(&ld_tree_lk);
301 
302 	if (lo->lo_sleeplock) {
303 		ld->ld_flags = LD_SLEEPER;
304 		lockdebug_unlock(&ld_sleeper_lk);
305 	} else {
306 		ld->ld_flags = 0;
307 		lockdebug_unlock(&ld_spinner_lk);
308 	}
309 
310 	return true;
311 }
312 
313 /*
314  * lockdebug_free:
315  *
316  *	A lock is being destroyed, so release debugging resources.
317  */
318 void
319 lockdebug_free(volatile void *lock)
320 {
321 	lockdebug_t *ld;
322 	lockdebuglk_t *lk;
323 
324 	if (panicstr != NULL)
325 		return;
326 
327 	ld = lockdebug_lookup(lock, &lk);
328 	if (ld == NULL) {
329 		panic("lockdebug_free: destroying uninitialized lock %p"
330 		    "(ld_lock=%p)", lock, ld->ld_lock);
331 		lockdebug_abort1(ld, lk, __func__, "lock record follows",
332 		    true);
333 	}
334 	if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0)
335 		lockdebug_abort1(ld, lk, __func__, "is locked", true);
336 	lockdebug_lock(&ld_tree_lk);
337 	rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
338 	lockdebug_unlock(&ld_tree_lk);
339 	ld->ld_lock = NULL;
340 	lockdebug_unlock(lk);
341 
342 	lockdebug_lock(&ld_free_lk);
343 	TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
344 	ld_nfree++;
345 	lockdebug_unlock(&ld_free_lk);
346 }
347 
348 /*
349  * lockdebug_more:
350  *
351  *	Allocate a batch of debug structures and add to the free list.
352  *	Must be called with ld_free_lk held.
353  */
354 static void
355 lockdebug_more(void)
356 {
357 	lockdebug_t *ld;
358 	void *block;
359 	int i, base, m;
360 
361 	while (ld_nfree < LD_SLOP) {
362 		lockdebug_unlock(&ld_free_lk);
363 		block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP);
364 		lockdebug_lock(&ld_free_lk);
365 
366 		if (block == NULL)
367 			return;
368 
369 		if (ld_nfree > LD_SLOP) {
370 			/* Somebody beat us to it. */
371 			lockdebug_unlock(&ld_free_lk);
372 			kmem_free(block, LD_BATCH * sizeof(lockdebug_t));
373 			lockdebug_lock(&ld_free_lk);
374 			continue;
375 		}
376 
377 		base = ld_freeptr;
378 		ld_nfree += LD_BATCH;
379 		ld = block;
380 		base <<= LD_BATCH_SHIFT;
381 		m = min(LD_MAX_LOCKS, base + LD_BATCH);
382 
383 		if (m == LD_MAX_LOCKS)
384 			ld_nomore = true;
385 
386 		for (i = base; i < m; i++, ld++) {
387 			TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
388 			TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
389 		}
390 
391 		mb_write();
392 		ld_table[ld_freeptr++] = block;
393 	}
394 }
395 
396 /*
397  * lockdebug_wantlock:
398  *
399  *	Process the preamble to a lock acquire.
400  */
401 void
402 lockdebug_wantlock(volatile void *lock, uintptr_t where, int shared)
403 {
404 	struct lwp *l = curlwp;
405 	lockdebuglk_t *lk;
406 	lockdebug_t *ld;
407 	bool recurse;
408 
409 	(void)shared;
410 	recurse = false;
411 
412 	if (panicstr != NULL)
413 		return;
414 
415 	if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
416 		return;
417 
418 	if ((ld->ld_flags & LD_LOCKED) != 0) {
419 		if ((ld->ld_flags & LD_SLEEPER) != 0) {
420 			if (ld->ld_lwp == l)
421 				recurse = true;
422 		} else if (ld->ld_cpu == (uint16_t)cpu_number())
423 			recurse = true;
424 	}
425 
426 #ifdef notyet
427 	if (cpu_intr_p()) {
428 		if ((ld->ld_flags & LD_SLEEPER) != 0)
429 			lockdebug_abort1(ld, lk, __func__,
430 			    "acquiring sleep lock from interrupt context",
431 			    true);
432 	}
433 #endif
434 
435 	if (shared)
436 		ld->ld_shwant++;
437 	else
438 		ld->ld_exwant++;
439 
440 	if (recurse)
441 		lockdebug_abort1(ld, lk, __func__, "locking against myself",
442 		    true);
443 
444 	lockdebug_unlock(lk);
445 }
446 
447 /*
448  * lockdebug_locked:
449  *
450  *	Process a lock acquire operation.
451  */
452 void
453 lockdebug_locked(volatile void *lock, uintptr_t where, int shared)
454 {
455 	struct lwp *l = curlwp;
456 	lockdebuglk_t *lk;
457 	lockdebug_t *ld;
458 
459 	if (panicstr != NULL)
460 		return;
461 
462 	if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
463 		return;
464 
465 	if (shared) {
466 		l->l_shlocks++;
467 		ld->ld_shares++;
468 		ld->ld_shwant--;
469 	} else {
470 		if ((ld->ld_flags & LD_LOCKED) != 0)
471 			lockdebug_abort1(ld, lk, __func__,
472 			    "already locked", true);
473 
474 		ld->ld_flags |= LD_LOCKED;
475 		ld->ld_locked = where;
476 		ld->ld_cpu = (uint16_t)cpu_number();
477 		ld->ld_lwp = l;
478 		ld->ld_exwant--;
479 
480 		if ((ld->ld_flags & LD_SLEEPER) != 0) {
481 			l->l_exlocks++;
482 			TAILQ_INSERT_TAIL(&ld_sleepers, ld, ld_chain);
483 		} else {
484 			curcpu()->ci_spin_locks2++;
485 			TAILQ_INSERT_TAIL(&ld_spinners, ld, ld_chain);
486 		}
487 	}
488 
489 	lockdebug_unlock(lk);
490 }
491 
492 /*
493  * lockdebug_unlocked:
494  *
495  *	Process a lock release operation.
496  */
497 void
498 lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared)
499 {
500 	struct lwp *l = curlwp;
501 	lockdebuglk_t *lk;
502 	lockdebug_t *ld;
503 
504 	if (panicstr != NULL)
505 		return;
506 
507 	if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
508 		return;
509 
510 	if (shared) {
511 		if (l->l_shlocks == 0)
512 			lockdebug_abort1(ld, lk, __func__,
513 			    "no shared locks held by LWP", true);
514 		if (ld->ld_shares == 0)
515 			lockdebug_abort1(ld, lk, __func__,
516 			    "no shared holds on this lock", true);
517 		l->l_shlocks--;
518 		ld->ld_shares--;
519 	} else {
520 		if ((ld->ld_flags & LD_LOCKED) == 0)
521 			lockdebug_abort1(ld, lk, __func__, "not locked",
522 			    true);
523 
524 		if ((ld->ld_flags & LD_SLEEPER) != 0) {
525 			if (ld->ld_lwp != curlwp)
526 				lockdebug_abort1(ld, lk, __func__,
527 				    "not held by current LWP", true);
528 			ld->ld_flags &= ~LD_LOCKED;
529 			ld->ld_unlocked = where;
530 			ld->ld_lwp = NULL;
531 			curlwp->l_exlocks--;
532 			TAILQ_REMOVE(&ld_sleepers, ld, ld_chain);
533 		} else {
534 			if (ld->ld_cpu != (uint16_t)cpu_number())
535 				lockdebug_abort1(ld, lk, __func__,
536 				    "not held by current CPU", true);
537 			ld->ld_flags &= ~LD_LOCKED;
538 			ld->ld_unlocked = where;
539 			ld->ld_lwp = NULL;
540 			curcpu()->ci_spin_locks2--;
541 			TAILQ_REMOVE(&ld_spinners, ld, ld_chain);
542 		}
543 	}
544 
545 	lockdebug_unlock(lk);
546 }
547 
548 /*
549  * lockdebug_barrier:
550  *
551  *	Panic if we hold more than one specified spin lock, and optionally,
552  *	if we hold sleep locks.
553  */
554 void
555 lockdebug_barrier(volatile void *spinlock, int slplocks)
556 {
557 	struct lwp *l = curlwp;
558 	lockdebug_t *ld;
559 	uint16_t cpuno;
560 
561 	if (panicstr != NULL)
562 		return;
563 
564 	if (curcpu()->ci_spin_locks2 != 0) {
565 		cpuno = (uint16_t)cpu_number();
566 
567 		lockdebug_lock(&ld_spinner_lk);
568 		TAILQ_FOREACH(ld, &ld_spinners, ld_chain) {
569 			if (ld->ld_lock == spinlock) {
570 				if (ld->ld_cpu != cpuno)
571 					lockdebug_abort1(ld, &ld_spinner_lk,
572 					    __func__,
573 					    "not held by current CPU", true);
574 				continue;
575 			}
576 			if (ld->ld_cpu == cpuno && (l->l_pflag & LP_INTR) == 0)
577 				lockdebug_abort1(ld, &ld_spinner_lk,
578 				    __func__, "spin lock held", true);
579 		}
580 		lockdebug_unlock(&ld_spinner_lk);
581 	}
582 
583 	if (!slplocks) {
584 		if (l->l_exlocks != 0) {
585 			lockdebug_lock(&ld_sleeper_lk);
586 			TAILQ_FOREACH(ld, &ld_sleepers, ld_chain) {
587 				if (ld->ld_lwp == l)
588 					lockdebug_abort1(ld, &ld_sleeper_lk,
589 					    __func__, "sleep lock held", true);
590 			}
591 			lockdebug_unlock(&ld_sleeper_lk);
592 		}
593 		if (l->l_shlocks != 0)
594 			panic("lockdebug_barrier: holding %d shared locks",
595 			    l->l_shlocks);
596 	}
597 }
598 
599 /*
600  * lockdebug_mem_check:
601  *
602  *	Check for in-use locks within a memory region that is
603  *	being freed.
604  */
605 void
606 lockdebug_mem_check(const char *func, void *base, size_t sz)
607 {
608 #if 0
609 	lockdebug_t *ld;
610 	lockdebuglk_t *lk;
611 	uintptr_t lock;
612 
613 	lockdebug_lock(&ld_tree_lk);
614 	ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base);
615 	lockdebug_unlock(&ld_tree_lk);
616 	if (ld == NULL)
617 		return;
618 
619 	if ((ld->ld_flags & LD_SLEEPER) != 0)
620 		lk = &ld_sleeper_lk;
621 	else
622 		lk = &ld_spinner_lk;
623 
624 	lockdebug_lock(lk);
625 	lock = (uintptr_t)ld->ld_lock;
626 	if ((uintptr_t)base <= lock && lock < (uintptr_t)base + sz) {
627 		lockdebug_abort1(ld, lk, func,
628 		    "allocation contains active lock", !cold);
629 		return;
630 	}
631 	lockdebug_unlock(lk);
632 #endif
633 }
634 
635 /*
636  * lockdebug_dump:
637  *
638  *	Dump information about a lock on panic, or for DDB.
639  */
640 static void
641 lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...))
642 {
643 	int sleeper = (ld->ld_flags & LD_SLEEPER);
644 
645 	(*pr)(
646 	    "lock address : %#018lx type     : %18s\n"
647 	    "shared holds : %18u exclusive: %18u\n"
648 	    "shares wanted: %18u exclusive: %18u\n"
649 	    "current cpu  : %18u last held: %18u\n"
650 	    "current lwp  : %#018lx last held: %#018lx\n"
651 	    "last locked  : %#018lx unlocked : %#018lx\n"
652 	    "initialized  : %#018lx\n",
653 	    (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"),
654 	    (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0),
655 	    (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant,
656 	    (unsigned)cpu_number(), (unsigned)ld->ld_cpu,
657 	    (long)curlwp, (long)ld->ld_lwp,
658 	    (long)ld->ld_locked, (long)ld->ld_unlocked,
659 	    (long)ld->ld_initaddr);
660 
661 	if (ld->ld_lockops->lo_dump != NULL)
662 		(*ld->ld_lockops->lo_dump)(ld->ld_lock);
663 
664 	if (sleeper) {
665 		(*pr)("\n");
666 		turnstile_print(ld->ld_lock, pr);
667 	}
668 }
669 
670 /*
671  * lockdebug_dump:
672  *
673  *	Dump information about a known lock.
674  */
675 static void
676 lockdebug_abort1(lockdebug_t *ld, lockdebuglk_t *lk, const char *func,
677 		 const char *msg, bool dopanic)
678 {
679 
680 	printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name,
681 	    func, msg);
682 	lockdebug_dump(ld, printf_nolog);
683 	lockdebug_unlock(lk);
684 	printf_nolog("\n");
685 	if (dopanic)
686 		panic("LOCKDEBUG");
687 }
688 
689 #endif	/* LOCKDEBUG */
690 
691 /*
692  * lockdebug_lock_print:
693  *
694  *	Handle the DDB 'show lock' command.
695  */
696 #ifdef DDB
697 void
698 lockdebug_lock_print(void *addr, void (*pr)(const char *, ...))
699 {
700 #ifdef LOCKDEBUG
701 	lockdebug_t *ld;
702 
703 	TAILQ_FOREACH(ld, &ld_all, ld_achain) {
704 		if (ld->ld_lock == addr) {
705 			lockdebug_dump(ld, pr);
706 			return;
707 		}
708 	}
709 	(*pr)("Sorry, no record of a lock with address %p found.\n", addr);
710 #else
711 	(*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n");
712 #endif	/* LOCKDEBUG */
713 }
714 #endif	/* DDB */
715 
716 /*
717  * lockdebug_abort:
718  *
719  *	An error has been trapped - dump lock info and call panic().
720  */
721 void
722 lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func,
723 		const char *msg)
724 {
725 #ifdef LOCKDEBUG
726 	lockdebug_t *ld;
727 	lockdebuglk_t *lk;
728 
729 	if ((ld = lockdebug_lookup(lock, &lk)) != NULL) {
730 		lockdebug_abort1(ld, lk, func, msg, true);
731 		/* NOTREACHED */
732 	}
733 #endif	/* LOCKDEBUG */
734 
735 	printf_nolog("%s error: %s: %s\n\n"
736 	    "lock address : %#018lx\n"
737 	    "current cpu  : %18d\n"
738 	    "current lwp  : %#018lx\n",
739 	    ops->lo_name, func, msg, (long)lock, (int)cpu_number(),
740 	    (long)curlwp);
741 
742 	(*ops->lo_dump)(lock);
743 
744 	printf_nolog("\n");
745 	panic("lock error");
746 }
747