subr_lockdebug.c revision 1.20 1 1.20 yamt /* $NetBSD: subr_lockdebug.c,v 1.20 2007/11/22 10:47:37 yamt Exp $ */
2 1.2 ad
3 1.2 ad /*-
4 1.2 ad * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc.
5 1.2 ad * All rights reserved.
6 1.2 ad *
7 1.2 ad * This code is derived from software contributed to The NetBSD Foundation
8 1.2 ad * by Andrew Doran.
9 1.2 ad *
10 1.2 ad * Redistribution and use in source and binary forms, with or without
11 1.2 ad * modification, are permitted provided that the following conditions
12 1.2 ad * are met:
13 1.2 ad * 1. Redistributions of source code must retain the above copyright
14 1.2 ad * notice, this list of conditions and the following disclaimer.
15 1.2 ad * 2. Redistributions in binary form must reproduce the above copyright
16 1.2 ad * notice, this list of conditions and the following disclaimer in the
17 1.2 ad * documentation and/or other materials provided with the distribution.
18 1.2 ad * 3. All advertising materials mentioning features or use of this software
19 1.2 ad * must display the following acknowledgement:
20 1.2 ad * This product includes software developed by the NetBSD
21 1.2 ad * Foundation, Inc. and its contributors.
22 1.2 ad * 4. Neither the name of The NetBSD Foundation nor the names of its
23 1.2 ad * contributors may be used to endorse or promote products derived
24 1.2 ad * from this software without specific prior written permission.
25 1.2 ad *
26 1.2 ad * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 1.2 ad * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 1.2 ad * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 1.2 ad * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 1.2 ad * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 1.2 ad * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 1.2 ad * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 1.2 ad * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 1.2 ad * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 1.2 ad * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 1.2 ad * POSSIBILITY OF SUCH DAMAGE.
37 1.2 ad */
38 1.2 ad
39 1.2 ad /*
40 1.11 ad * Basic lock debugging code shared among lock primitives.
41 1.2 ad */
42 1.2 ad
43 1.9 dsl #include <sys/cdefs.h>
44 1.20 yamt __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.20 2007/11/22 10:47:37 yamt Exp $");
45 1.9 dsl
46 1.2 ad #include "opt_multiprocessor.h"
47 1.2 ad #include "opt_ddb.h"
48 1.2 ad
49 1.2 ad #include <sys/param.h>
50 1.2 ad #include <sys/proc.h>
51 1.2 ad #include <sys/systm.h>
52 1.10 ad #include <sys/kernel.h>
53 1.2 ad #include <sys/kmem.h>
54 1.2 ad #include <sys/lock.h>
55 1.2 ad #include <sys/lockdebug.h>
56 1.2 ad #include <sys/sleepq.h>
57 1.10 ad #include <sys/cpu.h>
58 1.2 ad
59 1.16 yamt #include <lib/libkern/rb.h>
60 1.16 yamt
61 1.2 ad #ifdef LOCKDEBUG
62 1.2 ad
63 1.2 ad #define LD_BATCH_SHIFT 9
64 1.2 ad #define LD_BATCH (1 << LD_BATCH_SHIFT)
65 1.2 ad #define LD_BATCH_MASK (LD_BATCH - 1)
66 1.2 ad #define LD_MAX_LOCKS 1048576
67 1.2 ad #define LD_SLOP 16
68 1.2 ad
69 1.2 ad #define LD_LOCKED 0x01
70 1.2 ad #define LD_SLEEPER 0x02
71 1.2 ad
72 1.2 ad typedef union lockdebuglk {
73 1.2 ad struct {
74 1.2 ad __cpu_simple_lock_t lku_lock;
75 1.2 ad int lku_oldspl;
76 1.2 ad } ul;
77 1.2 ad uint8_t lk_pad[64];
78 1.2 ad } volatile __aligned(64) lockdebuglk_t;
79 1.2 ad
80 1.2 ad #define lk_lock ul.lku_lock
81 1.2 ad #define lk_oldspl ul.lku_oldspl
82 1.2 ad
83 1.2 ad typedef struct lockdebug {
84 1.16 yamt struct rb_node ld_rb_node; /* must be the first member */
85 1.2 ad _TAILQ_ENTRY(struct lockdebug, volatile) ld_chain;
86 1.2 ad _TAILQ_ENTRY(struct lockdebug, volatile) ld_achain;
87 1.2 ad volatile void *ld_lock;
88 1.2 ad lockops_t *ld_lockops;
89 1.2 ad struct lwp *ld_lwp;
90 1.2 ad uintptr_t ld_locked;
91 1.2 ad uintptr_t ld_unlocked;
92 1.10 ad uintptr_t ld_initaddr;
93 1.2 ad uint16_t ld_shares;
94 1.2 ad uint16_t ld_cpu;
95 1.2 ad uint8_t ld_flags;
96 1.2 ad uint8_t ld_shwant; /* advisory */
97 1.2 ad uint8_t ld_exwant; /* advisory */
98 1.2 ad uint8_t ld_unused;
99 1.2 ad } volatile lockdebug_t;
100 1.2 ad
101 1.2 ad typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t;
102 1.2 ad
103 1.16 yamt lockdebuglk_t ld_tree_lk;
104 1.15 matt lockdebuglk_t ld_sleeper_lk;
105 1.15 matt lockdebuglk_t ld_spinner_lk;
106 1.15 matt lockdebuglk_t ld_free_lk;
107 1.2 ad
108 1.13 matt lockdebuglist_t ld_sleepers = TAILQ_HEAD_INITIALIZER(ld_sleepers);
109 1.13 matt lockdebuglist_t ld_spinners = TAILQ_HEAD_INITIALIZER(ld_spinners);
110 1.13 matt lockdebuglist_t ld_free = TAILQ_HEAD_INITIALIZER(ld_free);
111 1.13 matt lockdebuglist_t ld_all = TAILQ_HEAD_INITIALIZER(ld_all);
112 1.2 ad int ld_nfree;
113 1.2 ad int ld_freeptr;
114 1.2 ad int ld_recurse;
115 1.5 ad bool ld_nomore;
116 1.2 ad lockdebug_t *ld_table[LD_MAX_LOCKS / LD_BATCH];
117 1.2 ad
118 1.2 ad lockdebug_t ld_prime[LD_BATCH];
119 1.2 ad
120 1.5 ad static void lockdebug_abort1(lockdebug_t *, lockdebuglk_t *lk,
121 1.10 ad const char *, const char *, bool);
122 1.5 ad static void lockdebug_more(void);
123 1.5 ad static void lockdebug_init(void);
124 1.2 ad
125 1.16 yamt static signed int
126 1.16 yamt ld_rb_compare_nodes(const struct rb_node *n1, const struct rb_node *n2)
127 1.16 yamt {
128 1.16 yamt const lockdebug_t *ld1 = (const void *)n1;
129 1.16 yamt const lockdebug_t *ld2 = (const void *)n2;
130 1.20 yamt const uintptr_t a = (uintptr_t)ld1->ld_lock;
131 1.20 yamt const uintptr_t b = (uintptr_t)ld2->ld_lock;
132 1.20 yamt
133 1.20 yamt if (a < b)
134 1.20 yamt return 1;
135 1.20 yamt if (a > b)
136 1.16 yamt return -1;
137 1.16 yamt return 0;
138 1.16 yamt }
139 1.16 yamt
140 1.16 yamt static signed int
141 1.16 yamt ld_rb_compare_key(const struct rb_node *n, const void *key)
142 1.16 yamt {
143 1.16 yamt const lockdebug_t *ld = (const void *)n;
144 1.20 yamt const uintptr_t a = (uintptr_t)ld->ld_lock;
145 1.20 yamt const uintptr_t b = (uintptr_t)key;
146 1.20 yamt
147 1.20 yamt if (a < b)
148 1.20 yamt return 1;
149 1.20 yamt if (a > b)
150 1.16 yamt return -1;
151 1.16 yamt return 0;
152 1.16 yamt }
153 1.16 yamt
154 1.16 yamt static struct rb_tree ld_rb_tree;
155 1.16 yamt
156 1.16 yamt static const struct rb_tree_ops ld_rb_tree_ops = {
157 1.16 yamt .rb_compare_nodes = ld_rb_compare_nodes,
158 1.16 yamt .rb_compare_key = ld_rb_compare_key,
159 1.16 yamt };
160 1.16 yamt
161 1.2 ad static inline void
162 1.2 ad lockdebug_lock(lockdebuglk_t *lk)
163 1.2 ad {
164 1.2 ad int s;
165 1.2 ad
166 1.8 ad s = splhigh();
167 1.2 ad __cpu_simple_lock(&lk->lk_lock);
168 1.2 ad lk->lk_oldspl = s;
169 1.2 ad }
170 1.2 ad
171 1.2 ad static inline void
172 1.2 ad lockdebug_unlock(lockdebuglk_t *lk)
173 1.2 ad {
174 1.2 ad int s;
175 1.2 ad
176 1.2 ad s = lk->lk_oldspl;
177 1.2 ad __cpu_simple_unlock(&(lk->lk_lock));
178 1.2 ad splx(s);
179 1.2 ad }
180 1.2 ad
181 1.2 ad static inline lockdebug_t *
182 1.19 yamt lockdebug_lookup1(volatile void *lock, lockdebuglk_t **lk)
183 1.2 ad {
184 1.16 yamt lockdebug_t *ld;
185 1.2 ad
186 1.16 yamt lockdebug_lock(&ld_tree_lk);
187 1.16 yamt ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock));
188 1.16 yamt lockdebug_unlock(&ld_tree_lk);
189 1.16 yamt if (ld == NULL)
190 1.19 yamt return NULL;
191 1.2 ad
192 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0)
193 1.2 ad *lk = &ld_sleeper_lk;
194 1.2 ad else
195 1.2 ad *lk = &ld_spinner_lk;
196 1.2 ad
197 1.2 ad lockdebug_lock(*lk);
198 1.2 ad return ld;
199 1.2 ad }
200 1.2 ad
201 1.2 ad /*
202 1.19 yamt * lockdebug_lookup:
203 1.19 yamt *
204 1.19 yamt * Find a lockdebug structure by a pointer to a lock and return it locked.
205 1.19 yamt */
206 1.19 yamt static inline lockdebug_t *
207 1.19 yamt lockdebug_lookup(volatile void *lock, lockdebuglk_t **lk)
208 1.19 yamt {
209 1.19 yamt lockdebug_t *ld;
210 1.19 yamt
211 1.19 yamt ld = lockdebug_lookup1(lock, lk);
212 1.19 yamt if (ld == NULL)
213 1.19 yamt panic("lockdebug_lookup: uninitialized lock (lock=%p)", lock);
214 1.19 yamt return ld;
215 1.19 yamt }
216 1.19 yamt
217 1.19 yamt /*
218 1.2 ad * lockdebug_init:
219 1.2 ad *
220 1.2 ad * Initialize the lockdebug system. Allocate an initial pool of
221 1.2 ad * lockdebug structures before the VM system is up and running.
222 1.2 ad */
223 1.5 ad static void
224 1.2 ad lockdebug_init(void)
225 1.2 ad {
226 1.2 ad lockdebug_t *ld;
227 1.2 ad int i;
228 1.2 ad
229 1.16 yamt __cpu_simple_lock_init(&ld_tree_lk.lk_lock);
230 1.15 matt __cpu_simple_lock_init(&ld_sleeper_lk.lk_lock);
231 1.15 matt __cpu_simple_lock_init(&ld_spinner_lk.lk_lock);
232 1.15 matt __cpu_simple_lock_init(&ld_free_lk.lk_lock);
233 1.15 matt
234 1.16 yamt rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops);
235 1.16 yamt
236 1.2 ad ld = ld_prime;
237 1.2 ad ld_table[0] = ld;
238 1.2 ad for (i = 1, ld++; i < LD_BATCH; i++, ld++) {
239 1.2 ad TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
240 1.2 ad TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
241 1.2 ad }
242 1.2 ad ld_freeptr = 1;
243 1.2 ad ld_nfree = LD_BATCH - 1;
244 1.2 ad }
245 1.2 ad
246 1.2 ad /*
247 1.2 ad * lockdebug_alloc:
248 1.2 ad *
249 1.2 ad * A lock is being initialized, so allocate an associated debug
250 1.2 ad * structure.
251 1.2 ad */
252 1.16 yamt bool
253 1.10 ad lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr)
254 1.2 ad {
255 1.2 ad struct cpu_info *ci;
256 1.2 ad lockdebug_t *ld;
257 1.19 yamt lockdebuglk_t *lk;
258 1.2 ad
259 1.5 ad if (lo == NULL || panicstr != NULL)
260 1.16 yamt return false;
261 1.5 ad if (ld_freeptr == 0)
262 1.5 ad lockdebug_init();
263 1.2 ad
264 1.19 yamt if ((ld = lockdebug_lookup1(lock, &lk)) != NULL) {
265 1.19 yamt lockdebug_abort1(ld, lk, __func__, "already initialized", true);
266 1.19 yamt /* NOTREACHED */
267 1.19 yamt }
268 1.19 yamt
269 1.2 ad ci = curcpu();
270 1.2 ad
271 1.2 ad /*
272 1.2 ad * Pinch a new debug structure. We may recurse because we call
273 1.2 ad * kmem_alloc(), which may need to initialize new locks somewhere
274 1.7 skrll * down the path. If not recursing, we try to maintain at least
275 1.2 ad * LD_SLOP structures free, which should hopefully be enough to
276 1.2 ad * satisfy kmem_alloc(). If we can't provide a structure, not to
277 1.2 ad * worry: we'll just mark the lock as not having an ID.
278 1.2 ad */
279 1.2 ad lockdebug_lock(&ld_free_lk);
280 1.2 ad ci->ci_lkdebug_recurse++;
281 1.2 ad
282 1.2 ad if (TAILQ_EMPTY(&ld_free)) {
283 1.5 ad if (ci->ci_lkdebug_recurse > 1 || ld_nomore) {
284 1.2 ad ci->ci_lkdebug_recurse--;
285 1.2 ad lockdebug_unlock(&ld_free_lk);
286 1.16 yamt return false;
287 1.2 ad }
288 1.2 ad lockdebug_more();
289 1.2 ad } else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP)
290 1.2 ad lockdebug_more();
291 1.2 ad
292 1.2 ad if ((ld = TAILQ_FIRST(&ld_free)) == NULL) {
293 1.2 ad lockdebug_unlock(&ld_free_lk);
294 1.16 yamt return false;
295 1.2 ad }
296 1.2 ad
297 1.2 ad TAILQ_REMOVE(&ld_free, ld, ld_chain);
298 1.2 ad ld_nfree--;
299 1.2 ad
300 1.2 ad ci->ci_lkdebug_recurse--;
301 1.2 ad lockdebug_unlock(&ld_free_lk);
302 1.2 ad
303 1.2 ad if (ld->ld_lock != NULL)
304 1.2 ad panic("lockdebug_alloc: corrupt table");
305 1.2 ad
306 1.2 ad if (lo->lo_sleeplock)
307 1.2 ad lockdebug_lock(&ld_sleeper_lk);
308 1.2 ad else
309 1.2 ad lockdebug_lock(&ld_spinner_lk);
310 1.2 ad
311 1.2 ad /* Initialise the structure. */
312 1.2 ad ld->ld_lock = lock;
313 1.2 ad ld->ld_lockops = lo;
314 1.2 ad ld->ld_locked = 0;
315 1.2 ad ld->ld_unlocked = 0;
316 1.2 ad ld->ld_lwp = NULL;
317 1.10 ad ld->ld_initaddr = initaddr;
318 1.2 ad
319 1.16 yamt lockdebug_lock(&ld_tree_lk);
320 1.16 yamt rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
321 1.16 yamt lockdebug_unlock(&ld_tree_lk);
322 1.16 yamt
323 1.2 ad if (lo->lo_sleeplock) {
324 1.2 ad ld->ld_flags = LD_SLEEPER;
325 1.2 ad lockdebug_unlock(&ld_sleeper_lk);
326 1.2 ad } else {
327 1.2 ad ld->ld_flags = 0;
328 1.2 ad lockdebug_unlock(&ld_spinner_lk);
329 1.2 ad }
330 1.2 ad
331 1.16 yamt return true;
332 1.2 ad }
333 1.2 ad
334 1.2 ad /*
335 1.2 ad * lockdebug_free:
336 1.2 ad *
337 1.2 ad * A lock is being destroyed, so release debugging resources.
338 1.2 ad */
339 1.2 ad void
340 1.16 yamt lockdebug_free(volatile void *lock)
341 1.2 ad {
342 1.2 ad lockdebug_t *ld;
343 1.2 ad lockdebuglk_t *lk;
344 1.2 ad
345 1.2 ad if (panicstr != NULL)
346 1.2 ad return;
347 1.2 ad
348 1.16 yamt ld = lockdebug_lookup(lock, &lk);
349 1.16 yamt if (ld == NULL) {
350 1.2 ad panic("lockdebug_free: destroying uninitialized lock %p"
351 1.16 yamt "(ld_lock=%p)", lock, ld->ld_lock);
352 1.10 ad lockdebug_abort1(ld, lk, __func__, "lock record follows",
353 1.10 ad true);
354 1.2 ad }
355 1.2 ad if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0)
356 1.10 ad lockdebug_abort1(ld, lk, __func__, "is locked", true);
357 1.16 yamt lockdebug_lock(&ld_tree_lk);
358 1.16 yamt rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
359 1.16 yamt lockdebug_unlock(&ld_tree_lk);
360 1.2 ad ld->ld_lock = NULL;
361 1.2 ad lockdebug_unlock(lk);
362 1.2 ad
363 1.2 ad lockdebug_lock(&ld_free_lk);
364 1.2 ad TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
365 1.2 ad ld_nfree++;
366 1.2 ad lockdebug_unlock(&ld_free_lk);
367 1.2 ad }
368 1.2 ad
369 1.2 ad /*
370 1.2 ad * lockdebug_more:
371 1.2 ad *
372 1.2 ad * Allocate a batch of debug structures and add to the free list.
373 1.2 ad * Must be called with ld_free_lk held.
374 1.2 ad */
375 1.5 ad static void
376 1.2 ad lockdebug_more(void)
377 1.2 ad {
378 1.2 ad lockdebug_t *ld;
379 1.2 ad void *block;
380 1.5 ad int i, base, m;
381 1.2 ad
382 1.2 ad while (ld_nfree < LD_SLOP) {
383 1.2 ad lockdebug_unlock(&ld_free_lk);
384 1.2 ad block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP);
385 1.2 ad lockdebug_lock(&ld_free_lk);
386 1.2 ad
387 1.2 ad if (block == NULL)
388 1.2 ad return;
389 1.2 ad
390 1.2 ad if (ld_nfree > LD_SLOP) {
391 1.2 ad /* Somebody beat us to it. */
392 1.2 ad lockdebug_unlock(&ld_free_lk);
393 1.2 ad kmem_free(block, LD_BATCH * sizeof(lockdebug_t));
394 1.2 ad lockdebug_lock(&ld_free_lk);
395 1.2 ad continue;
396 1.2 ad }
397 1.2 ad
398 1.2 ad base = ld_freeptr;
399 1.2 ad ld_nfree += LD_BATCH;
400 1.2 ad ld = block;
401 1.2 ad base <<= LD_BATCH_SHIFT;
402 1.5 ad m = min(LD_MAX_LOCKS, base + LD_BATCH);
403 1.5 ad
404 1.5 ad if (m == LD_MAX_LOCKS)
405 1.5 ad ld_nomore = true;
406 1.2 ad
407 1.5 ad for (i = base; i < m; i++, ld++) {
408 1.2 ad TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
409 1.2 ad TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
410 1.2 ad }
411 1.2 ad
412 1.2 ad mb_write();
413 1.2 ad ld_table[ld_freeptr++] = block;
414 1.2 ad }
415 1.2 ad }
416 1.2 ad
417 1.2 ad /*
418 1.2 ad * lockdebug_wantlock:
419 1.2 ad *
420 1.2 ad * Process the preamble to a lock acquire.
421 1.2 ad */
422 1.2 ad void
423 1.16 yamt lockdebug_wantlock(volatile void *lock, uintptr_t where, int shared)
424 1.2 ad {
425 1.2 ad struct lwp *l = curlwp;
426 1.2 ad lockdebuglk_t *lk;
427 1.2 ad lockdebug_t *ld;
428 1.3 thorpej bool recurse;
429 1.2 ad
430 1.2 ad (void)shared;
431 1.4 thorpej recurse = false;
432 1.2 ad
433 1.2 ad if (panicstr != NULL)
434 1.2 ad return;
435 1.2 ad
436 1.16 yamt if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
437 1.2 ad return;
438 1.2 ad
439 1.2 ad if ((ld->ld_flags & LD_LOCKED) != 0) {
440 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0) {
441 1.2 ad if (ld->ld_lwp == l)
442 1.4 thorpej recurse = true;
443 1.2 ad } else if (ld->ld_cpu == (uint16_t)cpu_number())
444 1.4 thorpej recurse = true;
445 1.2 ad }
446 1.2 ad
447 1.10 ad #ifdef notyet
448 1.10 ad if (cpu_intr_p()) {
449 1.10 ad if ((ld->ld_flags & LD_SLEEPER) != 0)
450 1.10 ad lockdebug_abort1(ld, lk, __func__,
451 1.10 ad "acquiring sleep lock from interrupt context",
452 1.10 ad true);
453 1.10 ad }
454 1.10 ad #endif
455 1.10 ad
456 1.2 ad if (shared)
457 1.2 ad ld->ld_shwant++;
458 1.2 ad else
459 1.2 ad ld->ld_exwant++;
460 1.2 ad
461 1.2 ad if (recurse)
462 1.10 ad lockdebug_abort1(ld, lk, __func__, "locking against myself",
463 1.10 ad true);
464 1.2 ad
465 1.2 ad lockdebug_unlock(lk);
466 1.2 ad }
467 1.2 ad
468 1.2 ad /*
469 1.2 ad * lockdebug_locked:
470 1.2 ad *
471 1.2 ad * Process a lock acquire operation.
472 1.2 ad */
473 1.2 ad void
474 1.16 yamt lockdebug_locked(volatile void *lock, uintptr_t where, int shared)
475 1.2 ad {
476 1.2 ad struct lwp *l = curlwp;
477 1.2 ad lockdebuglk_t *lk;
478 1.2 ad lockdebug_t *ld;
479 1.2 ad
480 1.2 ad if (panicstr != NULL)
481 1.2 ad return;
482 1.2 ad
483 1.16 yamt if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
484 1.2 ad return;
485 1.2 ad
486 1.2 ad if (shared) {
487 1.2 ad l->l_shlocks++;
488 1.2 ad ld->ld_shares++;
489 1.2 ad ld->ld_shwant--;
490 1.2 ad } else {
491 1.2 ad if ((ld->ld_flags & LD_LOCKED) != 0)
492 1.2 ad lockdebug_abort1(ld, lk, __func__,
493 1.10 ad "already locked", true);
494 1.2 ad
495 1.2 ad ld->ld_flags |= LD_LOCKED;
496 1.2 ad ld->ld_locked = where;
497 1.2 ad ld->ld_cpu = (uint16_t)cpu_number();
498 1.2 ad ld->ld_lwp = l;
499 1.2 ad ld->ld_exwant--;
500 1.2 ad
501 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0) {
502 1.2 ad l->l_exlocks++;
503 1.2 ad TAILQ_INSERT_TAIL(&ld_sleepers, ld, ld_chain);
504 1.2 ad } else {
505 1.2 ad curcpu()->ci_spin_locks2++;
506 1.2 ad TAILQ_INSERT_TAIL(&ld_spinners, ld, ld_chain);
507 1.2 ad }
508 1.2 ad }
509 1.2 ad
510 1.2 ad lockdebug_unlock(lk);
511 1.2 ad }
512 1.2 ad
513 1.2 ad /*
514 1.2 ad * lockdebug_unlocked:
515 1.2 ad *
516 1.2 ad * Process a lock release operation.
517 1.2 ad */
518 1.2 ad void
519 1.16 yamt lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared)
520 1.2 ad {
521 1.2 ad struct lwp *l = curlwp;
522 1.2 ad lockdebuglk_t *lk;
523 1.2 ad lockdebug_t *ld;
524 1.2 ad
525 1.2 ad if (panicstr != NULL)
526 1.2 ad return;
527 1.2 ad
528 1.16 yamt if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
529 1.2 ad return;
530 1.2 ad
531 1.2 ad if (shared) {
532 1.2 ad if (l->l_shlocks == 0)
533 1.2 ad lockdebug_abort1(ld, lk, __func__,
534 1.10 ad "no shared locks held by LWP", true);
535 1.2 ad if (ld->ld_shares == 0)
536 1.2 ad lockdebug_abort1(ld, lk, __func__,
537 1.10 ad "no shared holds on this lock", true);
538 1.2 ad l->l_shlocks--;
539 1.2 ad ld->ld_shares--;
540 1.2 ad } else {
541 1.2 ad if ((ld->ld_flags & LD_LOCKED) == 0)
542 1.10 ad lockdebug_abort1(ld, lk, __func__, "not locked",
543 1.10 ad true);
544 1.2 ad
545 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0) {
546 1.2 ad if (ld->ld_lwp != curlwp)
547 1.2 ad lockdebug_abort1(ld, lk, __func__,
548 1.10 ad "not held by current LWP", true);
549 1.2 ad ld->ld_flags &= ~LD_LOCKED;
550 1.2 ad ld->ld_unlocked = where;
551 1.2 ad ld->ld_lwp = NULL;
552 1.2 ad curlwp->l_exlocks--;
553 1.2 ad TAILQ_REMOVE(&ld_sleepers, ld, ld_chain);
554 1.2 ad } else {
555 1.2 ad if (ld->ld_cpu != (uint16_t)cpu_number())
556 1.2 ad lockdebug_abort1(ld, lk, __func__,
557 1.10 ad "not held by current CPU", true);
558 1.2 ad ld->ld_flags &= ~LD_LOCKED;
559 1.2 ad ld->ld_unlocked = where;
560 1.2 ad ld->ld_lwp = NULL;
561 1.2 ad curcpu()->ci_spin_locks2--;
562 1.2 ad TAILQ_REMOVE(&ld_spinners, ld, ld_chain);
563 1.2 ad }
564 1.2 ad }
565 1.2 ad
566 1.2 ad lockdebug_unlock(lk);
567 1.2 ad }
568 1.2 ad
569 1.2 ad /*
570 1.2 ad * lockdebug_barrier:
571 1.2 ad *
572 1.2 ad * Panic if we hold more than one specified spin lock, and optionally,
573 1.2 ad * if we hold sleep locks.
574 1.2 ad */
575 1.2 ad void
576 1.2 ad lockdebug_barrier(volatile void *spinlock, int slplocks)
577 1.2 ad {
578 1.2 ad struct lwp *l = curlwp;
579 1.2 ad lockdebug_t *ld;
580 1.2 ad uint16_t cpuno;
581 1.2 ad
582 1.2 ad if (panicstr != NULL)
583 1.2 ad return;
584 1.2 ad
585 1.2 ad if (curcpu()->ci_spin_locks2 != 0) {
586 1.2 ad cpuno = (uint16_t)cpu_number();
587 1.2 ad
588 1.2 ad lockdebug_lock(&ld_spinner_lk);
589 1.2 ad TAILQ_FOREACH(ld, &ld_spinners, ld_chain) {
590 1.2 ad if (ld->ld_lock == spinlock) {
591 1.2 ad if (ld->ld_cpu != cpuno)
592 1.2 ad lockdebug_abort1(ld, &ld_spinner_lk,
593 1.2 ad __func__,
594 1.10 ad "not held by current CPU", true);
595 1.2 ad continue;
596 1.2 ad }
597 1.12 ad if (ld->ld_cpu == cpuno && (l->l_pflag & LP_INTR) == 0)
598 1.2 ad lockdebug_abort1(ld, &ld_spinner_lk,
599 1.10 ad __func__, "spin lock held", true);
600 1.2 ad }
601 1.2 ad lockdebug_unlock(&ld_spinner_lk);
602 1.2 ad }
603 1.2 ad
604 1.2 ad if (!slplocks) {
605 1.2 ad if (l->l_exlocks != 0) {
606 1.2 ad lockdebug_lock(&ld_sleeper_lk);
607 1.2 ad TAILQ_FOREACH(ld, &ld_sleepers, ld_chain) {
608 1.2 ad if (ld->ld_lwp == l)
609 1.2 ad lockdebug_abort1(ld, &ld_sleeper_lk,
610 1.10 ad __func__, "sleep lock held", true);
611 1.2 ad }
612 1.2 ad lockdebug_unlock(&ld_sleeper_lk);
613 1.2 ad }
614 1.2 ad if (l->l_shlocks != 0)
615 1.2 ad panic("lockdebug_barrier: holding %d shared locks",
616 1.2 ad l->l_shlocks);
617 1.2 ad }
618 1.2 ad }
619 1.2 ad
620 1.2 ad /*
621 1.10 ad * lockdebug_mem_check:
622 1.10 ad *
623 1.10 ad * Check for in-use locks within a memory region that is
624 1.16 yamt * being freed.
625 1.10 ad */
626 1.10 ad void
627 1.10 ad lockdebug_mem_check(const char *func, void *base, size_t sz)
628 1.10 ad {
629 1.16 yamt lockdebug_t *ld;
630 1.10 ad lockdebuglk_t *lk;
631 1.16 yamt uintptr_t lock;
632 1.10 ad
633 1.16 yamt lockdebug_lock(&ld_tree_lk);
634 1.16 yamt ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base);
635 1.16 yamt lockdebug_unlock(&ld_tree_lk);
636 1.16 yamt if (ld == NULL)
637 1.16 yamt return;
638 1.16 yamt
639 1.16 yamt if ((ld->ld_flags & LD_SLEEPER) != 0)
640 1.16 yamt lk = &ld_sleeper_lk;
641 1.16 yamt else
642 1.16 yamt lk = &ld_spinner_lk;
643 1.10 ad
644 1.16 yamt lockdebug_lock(lk);
645 1.16 yamt lock = (uintptr_t)ld->ld_lock;
646 1.16 yamt if ((uintptr_t)base <= lock && lock < (uintptr_t)base + sz) {
647 1.16 yamt lockdebug_abort1(ld, lk, func,
648 1.16 yamt "allocation contains active lock", !cold);
649 1.16 yamt return;
650 1.10 ad }
651 1.10 ad lockdebug_unlock(lk);
652 1.10 ad }
653 1.10 ad
654 1.10 ad /*
655 1.2 ad * lockdebug_dump:
656 1.2 ad *
657 1.2 ad * Dump information about a lock on panic, or for DDB.
658 1.2 ad */
659 1.2 ad static void
660 1.2 ad lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...))
661 1.2 ad {
662 1.2 ad int sleeper = (ld->ld_flags & LD_SLEEPER);
663 1.2 ad
664 1.2 ad (*pr)(
665 1.2 ad "lock address : %#018lx type : %18s\n"
666 1.2 ad "shared holds : %18u exclusive: %18u\n"
667 1.2 ad "shares wanted: %18u exclusive: %18u\n"
668 1.2 ad "current cpu : %18u last held: %18u\n"
669 1.2 ad "current lwp : %#018lx last held: %#018lx\n"
670 1.10 ad "last locked : %#018lx unlocked : %#018lx\n"
671 1.10 ad "initialized : %#018lx\n",
672 1.2 ad (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"),
673 1.2 ad (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0),
674 1.2 ad (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant,
675 1.2 ad (unsigned)cpu_number(), (unsigned)ld->ld_cpu,
676 1.2 ad (long)curlwp, (long)ld->ld_lwp,
677 1.10 ad (long)ld->ld_locked, (long)ld->ld_unlocked,
678 1.10 ad (long)ld->ld_initaddr);
679 1.2 ad
680 1.2 ad if (ld->ld_lockops->lo_dump != NULL)
681 1.2 ad (*ld->ld_lockops->lo_dump)(ld->ld_lock);
682 1.2 ad
683 1.2 ad if (sleeper) {
684 1.2 ad (*pr)("\n");
685 1.2 ad turnstile_print(ld->ld_lock, pr);
686 1.2 ad }
687 1.2 ad }
688 1.2 ad
689 1.2 ad /*
690 1.2 ad * lockdebug_dump:
691 1.2 ad *
692 1.2 ad * Dump information about a known lock.
693 1.2 ad */
694 1.5 ad static void
695 1.2 ad lockdebug_abort1(lockdebug_t *ld, lockdebuglk_t *lk, const char *func,
696 1.10 ad const char *msg, bool dopanic)
697 1.2 ad {
698 1.2 ad
699 1.2 ad printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name,
700 1.2 ad func, msg);
701 1.2 ad lockdebug_dump(ld, printf_nolog);
702 1.2 ad lockdebug_unlock(lk);
703 1.2 ad printf_nolog("\n");
704 1.10 ad if (dopanic)
705 1.10 ad panic("LOCKDEBUG");
706 1.2 ad }
707 1.2 ad
708 1.2 ad #endif /* LOCKDEBUG */
709 1.2 ad
710 1.2 ad /*
711 1.2 ad * lockdebug_lock_print:
712 1.2 ad *
713 1.2 ad * Handle the DDB 'show lock' command.
714 1.2 ad */
715 1.2 ad #ifdef DDB
716 1.2 ad void
717 1.2 ad lockdebug_lock_print(void *addr, void (*pr)(const char *, ...))
718 1.2 ad {
719 1.2 ad #ifdef LOCKDEBUG
720 1.2 ad lockdebug_t *ld;
721 1.2 ad
722 1.2 ad TAILQ_FOREACH(ld, &ld_all, ld_achain) {
723 1.2 ad if (ld->ld_lock == addr) {
724 1.2 ad lockdebug_dump(ld, pr);
725 1.2 ad return;
726 1.2 ad }
727 1.2 ad }
728 1.2 ad (*pr)("Sorry, no record of a lock with address %p found.\n", addr);
729 1.2 ad #else
730 1.2 ad (*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n");
731 1.2 ad #endif /* LOCKDEBUG */
732 1.2 ad }
733 1.2 ad #endif /* DDB */
734 1.2 ad
735 1.2 ad /*
736 1.2 ad * lockdebug_abort:
737 1.2 ad *
738 1.2 ad * An error has been trapped - dump lock info and call panic().
739 1.2 ad */
740 1.2 ad void
741 1.16 yamt lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func,
742 1.16 yamt const char *msg)
743 1.2 ad {
744 1.2 ad #ifdef LOCKDEBUG
745 1.2 ad lockdebug_t *ld;
746 1.2 ad lockdebuglk_t *lk;
747 1.2 ad
748 1.16 yamt if ((ld = lockdebug_lookup(lock, &lk)) != NULL) {
749 1.10 ad lockdebug_abort1(ld, lk, func, msg, true);
750 1.2 ad /* NOTREACHED */
751 1.2 ad }
752 1.2 ad #endif /* LOCKDEBUG */
753 1.2 ad
754 1.2 ad printf_nolog("%s error: %s: %s\n\n"
755 1.2 ad "lock address : %#018lx\n"
756 1.2 ad "current cpu : %18d\n"
757 1.2 ad "current lwp : %#018lx\n",
758 1.2 ad ops->lo_name, func, msg, (long)lock, (int)cpu_number(),
759 1.2 ad (long)curlwp);
760 1.2 ad
761 1.2 ad (*ops->lo_dump)(lock);
762 1.2 ad
763 1.2 ad printf_nolog("\n");
764 1.2 ad panic("lock error");
765 1.2 ad }
766