subr_lockdebug.c revision 1.11.2.2 1 1.11.2.2 mjf /* $NetBSD: subr_lockdebug.c,v 1.11.2.2 2007/12/08 18:20:36 mjf 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 1.11.2.2 mjf __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.11.2.2 2007/12/08 18:20:36 mjf 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 1.11.2.2 mjf #include <sys/atomic.h>
59 1.11.2.2 mjf
60 1.11.2.2 mjf #include <lib/libkern/rb.h>
61 1.2 ad
62 1.2 ad #ifdef LOCKDEBUG
63 1.2 ad
64 1.2 ad #define LD_BATCH_SHIFT 9
65 1.2 ad #define LD_BATCH (1 << LD_BATCH_SHIFT)
66 1.2 ad #define LD_BATCH_MASK (LD_BATCH - 1)
67 1.2 ad #define LD_MAX_LOCKS 1048576
68 1.2 ad #define LD_SLOP 16
69 1.2 ad
70 1.2 ad #define LD_LOCKED 0x01
71 1.2 ad #define LD_SLEEPER 0x02
72 1.2 ad
73 1.2 ad typedef union lockdebuglk {
74 1.2 ad struct {
75 1.2 ad __cpu_simple_lock_t lku_lock;
76 1.2 ad int lku_oldspl;
77 1.2 ad } ul;
78 1.2 ad uint8_t lk_pad[64];
79 1.2 ad } volatile __aligned(64) lockdebuglk_t;
80 1.2 ad
81 1.2 ad #define lk_lock ul.lku_lock
82 1.2 ad #define lk_oldspl ul.lku_oldspl
83 1.2 ad
84 1.2 ad typedef struct lockdebug {
85 1.11.2.2 mjf struct rb_node ld_rb_node; /* must be the first member */
86 1.2 ad _TAILQ_ENTRY(struct lockdebug, volatile) ld_chain;
87 1.2 ad _TAILQ_ENTRY(struct lockdebug, volatile) ld_achain;
88 1.2 ad volatile void *ld_lock;
89 1.2 ad lockops_t *ld_lockops;
90 1.2 ad struct lwp *ld_lwp;
91 1.2 ad uintptr_t ld_locked;
92 1.2 ad uintptr_t ld_unlocked;
93 1.10 ad uintptr_t ld_initaddr;
94 1.2 ad uint16_t ld_shares;
95 1.2 ad uint16_t ld_cpu;
96 1.2 ad uint8_t ld_flags;
97 1.2 ad uint8_t ld_shwant; /* advisory */
98 1.2 ad uint8_t ld_exwant; /* advisory */
99 1.2 ad uint8_t ld_unused;
100 1.2 ad } volatile lockdebug_t;
101 1.2 ad
102 1.2 ad typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t;
103 1.2 ad
104 1.11.2.2 mjf lockdebuglk_t ld_tree_lk;
105 1.2 ad lockdebuglk_t ld_sleeper_lk;
106 1.2 ad lockdebuglk_t ld_spinner_lk;
107 1.2 ad lockdebuglk_t ld_free_lk;
108 1.2 ad
109 1.11.2.1 mjf lockdebuglist_t ld_sleepers = TAILQ_HEAD_INITIALIZER(ld_sleepers);
110 1.11.2.1 mjf lockdebuglist_t ld_spinners = TAILQ_HEAD_INITIALIZER(ld_spinners);
111 1.11.2.1 mjf lockdebuglist_t ld_free = TAILQ_HEAD_INITIALIZER(ld_free);
112 1.11.2.1 mjf lockdebuglist_t ld_all = TAILQ_HEAD_INITIALIZER(ld_all);
113 1.2 ad int ld_nfree;
114 1.2 ad int ld_freeptr;
115 1.2 ad int ld_recurse;
116 1.5 ad bool ld_nomore;
117 1.2 ad lockdebug_t *ld_table[LD_MAX_LOCKS / LD_BATCH];
118 1.2 ad
119 1.2 ad lockdebug_t ld_prime[LD_BATCH];
120 1.2 ad
121 1.5 ad static void lockdebug_abort1(lockdebug_t *, lockdebuglk_t *lk,
122 1.10 ad const char *, const char *, bool);
123 1.5 ad static void lockdebug_more(void);
124 1.5 ad static void lockdebug_init(void);
125 1.2 ad
126 1.11.2.2 mjf static signed int
127 1.11.2.2 mjf ld_rb_compare_nodes(const struct rb_node *n1, const struct rb_node *n2)
128 1.11.2.2 mjf {
129 1.11.2.2 mjf const lockdebug_t *ld1 = (const void *)n1;
130 1.11.2.2 mjf const lockdebug_t *ld2 = (const void *)n2;
131 1.11.2.2 mjf const uintptr_t a = (uintptr_t)ld1->ld_lock;
132 1.11.2.2 mjf const uintptr_t b = (uintptr_t)ld2->ld_lock;
133 1.11.2.2 mjf
134 1.11.2.2 mjf if (a < b)
135 1.11.2.2 mjf return 1;
136 1.11.2.2 mjf if (a > b)
137 1.11.2.2 mjf return -1;
138 1.11.2.2 mjf return 0;
139 1.11.2.2 mjf }
140 1.11.2.2 mjf
141 1.11.2.2 mjf static signed int
142 1.11.2.2 mjf ld_rb_compare_key(const struct rb_node *n, const void *key)
143 1.11.2.2 mjf {
144 1.11.2.2 mjf const lockdebug_t *ld = (const void *)n;
145 1.11.2.2 mjf const uintptr_t a = (uintptr_t)ld->ld_lock;
146 1.11.2.2 mjf const uintptr_t b = (uintptr_t)key;
147 1.11.2.2 mjf
148 1.11.2.2 mjf if (a < b)
149 1.11.2.2 mjf return 1;
150 1.11.2.2 mjf if (a > b)
151 1.11.2.2 mjf return -1;
152 1.11.2.2 mjf return 0;
153 1.11.2.2 mjf }
154 1.11.2.2 mjf
155 1.11.2.2 mjf static struct rb_tree ld_rb_tree;
156 1.11.2.2 mjf
157 1.11.2.2 mjf static const struct rb_tree_ops ld_rb_tree_ops = {
158 1.11.2.2 mjf .rb_compare_nodes = ld_rb_compare_nodes,
159 1.11.2.2 mjf .rb_compare_key = ld_rb_compare_key,
160 1.11.2.2 mjf };
161 1.11.2.2 mjf
162 1.2 ad static inline void
163 1.2 ad lockdebug_lock(lockdebuglk_t *lk)
164 1.2 ad {
165 1.2 ad int s;
166 1.2 ad
167 1.8 ad s = splhigh();
168 1.2 ad __cpu_simple_lock(&lk->lk_lock);
169 1.2 ad lk->lk_oldspl = s;
170 1.2 ad }
171 1.2 ad
172 1.2 ad static inline void
173 1.2 ad lockdebug_unlock(lockdebuglk_t *lk)
174 1.2 ad {
175 1.2 ad int s;
176 1.2 ad
177 1.2 ad s = lk->lk_oldspl;
178 1.2 ad __cpu_simple_unlock(&(lk->lk_lock));
179 1.2 ad splx(s);
180 1.2 ad }
181 1.2 ad
182 1.11.2.2 mjf static inline lockdebug_t *
183 1.11.2.2 mjf lockdebug_lookup1(volatile void *lock, lockdebuglk_t **lk)
184 1.10 ad {
185 1.11.2.2 mjf lockdebug_t *ld;
186 1.11.2.2 mjf
187 1.11.2.2 mjf lockdebug_lock(&ld_tree_lk);
188 1.11.2.2 mjf ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock));
189 1.11.2.2 mjf lockdebug_unlock(&ld_tree_lk);
190 1.11.2.2 mjf if (ld == NULL)
191 1.11.2.2 mjf return NULL;
192 1.11.2.2 mjf
193 1.11.2.2 mjf if ((ld->ld_flags & LD_SLEEPER) != 0)
194 1.11.2.2 mjf *lk = &ld_sleeper_lk;
195 1.11.2.2 mjf else
196 1.11.2.2 mjf *lk = &ld_spinner_lk;
197 1.10 ad
198 1.10 ad lockdebug_lock(*lk);
199 1.11.2.2 mjf return ld;
200 1.10 ad }
201 1.10 ad
202 1.2 ad /*
203 1.2 ad * lockdebug_lookup:
204 1.2 ad *
205 1.11.2.2 mjf * Find a lockdebug structure by a pointer to a lock and return it locked.
206 1.2 ad */
207 1.2 ad static inline lockdebug_t *
208 1.11.2.2 mjf lockdebug_lookup(volatile void *lock, lockdebuglk_t **lk)
209 1.2 ad {
210 1.11.2.2 mjf lockdebug_t *ld;
211 1.2 ad
212 1.11.2.2 mjf ld = lockdebug_lookup1(lock, lk);
213 1.11.2.2 mjf if (ld == NULL)
214 1.11.2.2 mjf panic("lockdebug_lookup: uninitialized lock (lock=%p)", lock);
215 1.2 ad return ld;
216 1.2 ad }
217 1.2 ad
218 1.2 ad /*
219 1.2 ad * lockdebug_init:
220 1.2 ad *
221 1.2 ad * Initialize the lockdebug system. Allocate an initial pool of
222 1.2 ad * lockdebug structures before the VM system is up and running.
223 1.2 ad */
224 1.5 ad static void
225 1.2 ad lockdebug_init(void)
226 1.2 ad {
227 1.2 ad lockdebug_t *ld;
228 1.2 ad int i;
229 1.2 ad
230 1.11.2.2 mjf __cpu_simple_lock_init(&ld_tree_lk.lk_lock);
231 1.2 ad __cpu_simple_lock_init(&ld_sleeper_lk.lk_lock);
232 1.2 ad __cpu_simple_lock_init(&ld_spinner_lk.lk_lock);
233 1.2 ad __cpu_simple_lock_init(&ld_free_lk.lk_lock);
234 1.2 ad
235 1.11.2.2 mjf rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops);
236 1.11.2.2 mjf
237 1.2 ad ld = ld_prime;
238 1.2 ad ld_table[0] = ld;
239 1.2 ad for (i = 1, ld++; i < LD_BATCH; i++, ld++) {
240 1.2 ad TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
241 1.2 ad TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
242 1.2 ad }
243 1.2 ad ld_freeptr = 1;
244 1.2 ad ld_nfree = LD_BATCH - 1;
245 1.2 ad }
246 1.2 ad
247 1.2 ad /*
248 1.2 ad * lockdebug_alloc:
249 1.2 ad *
250 1.2 ad * A lock is being initialized, so allocate an associated debug
251 1.2 ad * structure.
252 1.2 ad */
253 1.11.2.2 mjf bool
254 1.10 ad lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr)
255 1.2 ad {
256 1.2 ad struct cpu_info *ci;
257 1.2 ad lockdebug_t *ld;
258 1.11.2.2 mjf lockdebuglk_t *lk;
259 1.2 ad
260 1.5 ad if (lo == NULL || panicstr != NULL)
261 1.11.2.2 mjf return false;
262 1.5 ad if (ld_freeptr == 0)
263 1.5 ad lockdebug_init();
264 1.2 ad
265 1.11.2.2 mjf if ((ld = lockdebug_lookup1(lock, &lk)) != NULL) {
266 1.11.2.2 mjf lockdebug_abort1(ld, lk, __func__, "already initialized", true);
267 1.11.2.2 mjf /* NOTREACHED */
268 1.11.2.2 mjf }
269 1.11.2.2 mjf
270 1.2 ad ci = curcpu();
271 1.2 ad
272 1.2 ad /*
273 1.2 ad * Pinch a new debug structure. We may recurse because we call
274 1.2 ad * kmem_alloc(), which may need to initialize new locks somewhere
275 1.7 skrll * down the path. If not recursing, we try to maintain at least
276 1.2 ad * LD_SLOP structures free, which should hopefully be enough to
277 1.2 ad * satisfy kmem_alloc(). If we can't provide a structure, not to
278 1.2 ad * worry: we'll just mark the lock as not having an ID.
279 1.2 ad */
280 1.2 ad lockdebug_lock(&ld_free_lk);
281 1.2 ad ci->ci_lkdebug_recurse++;
282 1.2 ad
283 1.2 ad if (TAILQ_EMPTY(&ld_free)) {
284 1.5 ad if (ci->ci_lkdebug_recurse > 1 || ld_nomore) {
285 1.2 ad ci->ci_lkdebug_recurse--;
286 1.2 ad lockdebug_unlock(&ld_free_lk);
287 1.11.2.2 mjf return false;
288 1.2 ad }
289 1.2 ad lockdebug_more();
290 1.2 ad } else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP)
291 1.2 ad lockdebug_more();
292 1.2 ad
293 1.2 ad if ((ld = TAILQ_FIRST(&ld_free)) == NULL) {
294 1.2 ad lockdebug_unlock(&ld_free_lk);
295 1.11.2.2 mjf return false;
296 1.2 ad }
297 1.2 ad
298 1.2 ad TAILQ_REMOVE(&ld_free, ld, ld_chain);
299 1.2 ad ld_nfree--;
300 1.2 ad
301 1.2 ad ci->ci_lkdebug_recurse--;
302 1.2 ad lockdebug_unlock(&ld_free_lk);
303 1.2 ad
304 1.2 ad if (ld->ld_lock != NULL)
305 1.2 ad panic("lockdebug_alloc: corrupt table");
306 1.2 ad
307 1.2 ad if (lo->lo_sleeplock)
308 1.2 ad lockdebug_lock(&ld_sleeper_lk);
309 1.2 ad else
310 1.2 ad lockdebug_lock(&ld_spinner_lk);
311 1.2 ad
312 1.2 ad /* Initialise the structure. */
313 1.2 ad ld->ld_lock = lock;
314 1.2 ad ld->ld_lockops = lo;
315 1.2 ad ld->ld_locked = 0;
316 1.2 ad ld->ld_unlocked = 0;
317 1.2 ad ld->ld_lwp = NULL;
318 1.10 ad ld->ld_initaddr = initaddr;
319 1.2 ad
320 1.11.2.2 mjf lockdebug_lock(&ld_tree_lk);
321 1.11.2.2 mjf rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
322 1.11.2.2 mjf lockdebug_unlock(&ld_tree_lk);
323 1.11.2.2 mjf
324 1.2 ad if (lo->lo_sleeplock) {
325 1.2 ad ld->ld_flags = LD_SLEEPER;
326 1.2 ad lockdebug_unlock(&ld_sleeper_lk);
327 1.2 ad } else {
328 1.2 ad ld->ld_flags = 0;
329 1.2 ad lockdebug_unlock(&ld_spinner_lk);
330 1.2 ad }
331 1.2 ad
332 1.11.2.2 mjf return true;
333 1.2 ad }
334 1.2 ad
335 1.2 ad /*
336 1.2 ad * lockdebug_free:
337 1.2 ad *
338 1.2 ad * A lock is being destroyed, so release debugging resources.
339 1.2 ad */
340 1.2 ad void
341 1.11.2.2 mjf lockdebug_free(volatile void *lock)
342 1.2 ad {
343 1.2 ad lockdebug_t *ld;
344 1.2 ad lockdebuglk_t *lk;
345 1.2 ad
346 1.2 ad if (panicstr != NULL)
347 1.2 ad return;
348 1.2 ad
349 1.11.2.2 mjf ld = lockdebug_lookup(lock, &lk);
350 1.11.2.2 mjf if (ld == NULL) {
351 1.2 ad panic("lockdebug_free: destroying uninitialized lock %p"
352 1.11.2.2 mjf "(ld_lock=%p)", lock, ld->ld_lock);
353 1.10 ad lockdebug_abort1(ld, lk, __func__, "lock record follows",
354 1.10 ad true);
355 1.2 ad }
356 1.2 ad if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0)
357 1.10 ad lockdebug_abort1(ld, lk, __func__, "is locked", true);
358 1.11.2.2 mjf lockdebug_lock(&ld_tree_lk);
359 1.11.2.2 mjf rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
360 1.11.2.2 mjf lockdebug_unlock(&ld_tree_lk);
361 1.2 ad ld->ld_lock = NULL;
362 1.2 ad lockdebug_unlock(lk);
363 1.2 ad
364 1.2 ad lockdebug_lock(&ld_free_lk);
365 1.2 ad TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
366 1.2 ad ld_nfree++;
367 1.2 ad lockdebug_unlock(&ld_free_lk);
368 1.2 ad }
369 1.2 ad
370 1.2 ad /*
371 1.2 ad * lockdebug_more:
372 1.2 ad *
373 1.2 ad * Allocate a batch of debug structures and add to the free list.
374 1.2 ad * Must be called with ld_free_lk held.
375 1.2 ad */
376 1.5 ad static void
377 1.2 ad lockdebug_more(void)
378 1.2 ad {
379 1.2 ad lockdebug_t *ld;
380 1.2 ad void *block;
381 1.5 ad int i, base, m;
382 1.2 ad
383 1.2 ad while (ld_nfree < LD_SLOP) {
384 1.2 ad lockdebug_unlock(&ld_free_lk);
385 1.2 ad block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP);
386 1.2 ad lockdebug_lock(&ld_free_lk);
387 1.2 ad
388 1.2 ad if (block == NULL)
389 1.2 ad return;
390 1.2 ad
391 1.2 ad if (ld_nfree > LD_SLOP) {
392 1.2 ad /* Somebody beat us to it. */
393 1.2 ad lockdebug_unlock(&ld_free_lk);
394 1.2 ad kmem_free(block, LD_BATCH * sizeof(lockdebug_t));
395 1.2 ad lockdebug_lock(&ld_free_lk);
396 1.2 ad continue;
397 1.2 ad }
398 1.2 ad
399 1.2 ad base = ld_freeptr;
400 1.2 ad ld_nfree += LD_BATCH;
401 1.2 ad ld = block;
402 1.2 ad base <<= LD_BATCH_SHIFT;
403 1.5 ad m = min(LD_MAX_LOCKS, base + LD_BATCH);
404 1.5 ad
405 1.5 ad if (m == LD_MAX_LOCKS)
406 1.5 ad ld_nomore = true;
407 1.2 ad
408 1.5 ad for (i = base; i < m; i++, ld++) {
409 1.2 ad TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
410 1.2 ad TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
411 1.2 ad }
412 1.2 ad
413 1.11.2.2 mjf membar_producer();
414 1.2 ad ld_table[ld_freeptr++] = block;
415 1.2 ad }
416 1.2 ad }
417 1.2 ad
418 1.2 ad /*
419 1.2 ad * lockdebug_wantlock:
420 1.2 ad *
421 1.2 ad * Process the preamble to a lock acquire.
422 1.2 ad */
423 1.2 ad void
424 1.11.2.2 mjf lockdebug_wantlock(volatile void *lock, uintptr_t where, int shared)
425 1.2 ad {
426 1.2 ad struct lwp *l = curlwp;
427 1.2 ad lockdebuglk_t *lk;
428 1.2 ad lockdebug_t *ld;
429 1.3 thorpej bool recurse;
430 1.2 ad
431 1.2 ad (void)shared;
432 1.4 thorpej recurse = false;
433 1.2 ad
434 1.2 ad if (panicstr != NULL)
435 1.2 ad return;
436 1.2 ad
437 1.11.2.2 mjf if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
438 1.2 ad return;
439 1.2 ad
440 1.2 ad if ((ld->ld_flags & LD_LOCKED) != 0) {
441 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0) {
442 1.2 ad if (ld->ld_lwp == l)
443 1.4 thorpej recurse = true;
444 1.2 ad } else if (ld->ld_cpu == (uint16_t)cpu_number())
445 1.4 thorpej recurse = true;
446 1.2 ad }
447 1.2 ad
448 1.10 ad #ifdef notyet
449 1.10 ad if (cpu_intr_p()) {
450 1.10 ad if ((ld->ld_flags & LD_SLEEPER) != 0)
451 1.10 ad lockdebug_abort1(ld, lk, __func__,
452 1.10 ad "acquiring sleep lock from interrupt context",
453 1.10 ad true);
454 1.10 ad }
455 1.10 ad #endif
456 1.10 ad
457 1.2 ad if (shared)
458 1.2 ad ld->ld_shwant++;
459 1.2 ad else
460 1.2 ad ld->ld_exwant++;
461 1.2 ad
462 1.2 ad if (recurse)
463 1.10 ad lockdebug_abort1(ld, lk, __func__, "locking against myself",
464 1.10 ad true);
465 1.2 ad
466 1.2 ad lockdebug_unlock(lk);
467 1.2 ad }
468 1.2 ad
469 1.2 ad /*
470 1.2 ad * lockdebug_locked:
471 1.2 ad *
472 1.2 ad * Process a lock acquire operation.
473 1.2 ad */
474 1.2 ad void
475 1.11.2.2 mjf lockdebug_locked(volatile void *lock, uintptr_t where, int shared)
476 1.2 ad {
477 1.2 ad struct lwp *l = curlwp;
478 1.2 ad lockdebuglk_t *lk;
479 1.2 ad lockdebug_t *ld;
480 1.2 ad
481 1.2 ad if (panicstr != NULL)
482 1.2 ad return;
483 1.2 ad
484 1.11.2.2 mjf if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
485 1.2 ad return;
486 1.2 ad
487 1.2 ad if (shared) {
488 1.2 ad l->l_shlocks++;
489 1.2 ad ld->ld_shares++;
490 1.2 ad ld->ld_shwant--;
491 1.2 ad } else {
492 1.2 ad if ((ld->ld_flags & LD_LOCKED) != 0)
493 1.2 ad lockdebug_abort1(ld, lk, __func__,
494 1.10 ad "already locked", true);
495 1.2 ad
496 1.2 ad ld->ld_flags |= LD_LOCKED;
497 1.2 ad ld->ld_locked = where;
498 1.2 ad ld->ld_cpu = (uint16_t)cpu_number();
499 1.2 ad ld->ld_lwp = l;
500 1.2 ad ld->ld_exwant--;
501 1.2 ad
502 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0) {
503 1.2 ad l->l_exlocks++;
504 1.2 ad TAILQ_INSERT_TAIL(&ld_sleepers, ld, ld_chain);
505 1.2 ad } else {
506 1.2 ad curcpu()->ci_spin_locks2++;
507 1.2 ad TAILQ_INSERT_TAIL(&ld_spinners, ld, ld_chain);
508 1.2 ad }
509 1.2 ad }
510 1.2 ad
511 1.2 ad lockdebug_unlock(lk);
512 1.2 ad }
513 1.2 ad
514 1.2 ad /*
515 1.2 ad * lockdebug_unlocked:
516 1.2 ad *
517 1.2 ad * Process a lock release operation.
518 1.2 ad */
519 1.2 ad void
520 1.11.2.2 mjf lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared)
521 1.2 ad {
522 1.2 ad struct lwp *l = curlwp;
523 1.2 ad lockdebuglk_t *lk;
524 1.2 ad lockdebug_t *ld;
525 1.2 ad
526 1.2 ad if (panicstr != NULL)
527 1.2 ad return;
528 1.2 ad
529 1.11.2.2 mjf if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
530 1.2 ad return;
531 1.2 ad
532 1.2 ad if (shared) {
533 1.2 ad if (l->l_shlocks == 0)
534 1.2 ad lockdebug_abort1(ld, lk, __func__,
535 1.10 ad "no shared locks held by LWP", true);
536 1.2 ad if (ld->ld_shares == 0)
537 1.2 ad lockdebug_abort1(ld, lk, __func__,
538 1.10 ad "no shared holds on this lock", true);
539 1.2 ad l->l_shlocks--;
540 1.2 ad ld->ld_shares--;
541 1.2 ad } else {
542 1.2 ad if ((ld->ld_flags & LD_LOCKED) == 0)
543 1.10 ad lockdebug_abort1(ld, lk, __func__, "not locked",
544 1.10 ad true);
545 1.2 ad
546 1.2 ad if ((ld->ld_flags & LD_SLEEPER) != 0) {
547 1.2 ad if (ld->ld_lwp != curlwp)
548 1.2 ad lockdebug_abort1(ld, lk, __func__,
549 1.10 ad "not held by current LWP", true);
550 1.2 ad ld->ld_flags &= ~LD_LOCKED;
551 1.2 ad ld->ld_unlocked = where;
552 1.2 ad ld->ld_lwp = NULL;
553 1.2 ad curlwp->l_exlocks--;
554 1.2 ad TAILQ_REMOVE(&ld_sleepers, ld, ld_chain);
555 1.2 ad } else {
556 1.2 ad if (ld->ld_cpu != (uint16_t)cpu_number())
557 1.2 ad lockdebug_abort1(ld, lk, __func__,
558 1.10 ad "not held by current CPU", true);
559 1.2 ad ld->ld_flags &= ~LD_LOCKED;
560 1.2 ad ld->ld_unlocked = where;
561 1.2 ad ld->ld_lwp = NULL;
562 1.2 ad curcpu()->ci_spin_locks2--;
563 1.2 ad TAILQ_REMOVE(&ld_spinners, ld, ld_chain);
564 1.2 ad }
565 1.2 ad }
566 1.2 ad
567 1.2 ad lockdebug_unlock(lk);
568 1.2 ad }
569 1.2 ad
570 1.2 ad /*
571 1.2 ad * lockdebug_barrier:
572 1.2 ad *
573 1.2 ad * Panic if we hold more than one specified spin lock, and optionally,
574 1.2 ad * if we hold sleep locks.
575 1.2 ad */
576 1.2 ad void
577 1.2 ad lockdebug_barrier(volatile void *spinlock, int slplocks)
578 1.2 ad {
579 1.2 ad struct lwp *l = curlwp;
580 1.2 ad lockdebug_t *ld;
581 1.2 ad uint16_t cpuno;
582 1.2 ad
583 1.2 ad if (panicstr != NULL)
584 1.2 ad return;
585 1.2 ad
586 1.2 ad if (curcpu()->ci_spin_locks2 != 0) {
587 1.2 ad cpuno = (uint16_t)cpu_number();
588 1.2 ad
589 1.2 ad lockdebug_lock(&ld_spinner_lk);
590 1.2 ad TAILQ_FOREACH(ld, &ld_spinners, ld_chain) {
591 1.2 ad if (ld->ld_lock == spinlock) {
592 1.2 ad if (ld->ld_cpu != cpuno)
593 1.2 ad lockdebug_abort1(ld, &ld_spinner_lk,
594 1.2 ad __func__,
595 1.10 ad "not held by current CPU", true);
596 1.2 ad continue;
597 1.2 ad }
598 1.11.2.1 mjf if (ld->ld_cpu == cpuno && (l->l_pflag & LP_INTR) == 0)
599 1.2 ad lockdebug_abort1(ld, &ld_spinner_lk,
600 1.10 ad __func__, "spin lock held", true);
601 1.2 ad }
602 1.2 ad lockdebug_unlock(&ld_spinner_lk);
603 1.2 ad }
604 1.2 ad
605 1.2 ad if (!slplocks) {
606 1.2 ad if (l->l_exlocks != 0) {
607 1.2 ad lockdebug_lock(&ld_sleeper_lk);
608 1.2 ad TAILQ_FOREACH(ld, &ld_sleepers, ld_chain) {
609 1.2 ad if (ld->ld_lwp == l)
610 1.2 ad lockdebug_abort1(ld, &ld_sleeper_lk,
611 1.10 ad __func__, "sleep lock held", true);
612 1.2 ad }
613 1.2 ad lockdebug_unlock(&ld_sleeper_lk);
614 1.2 ad }
615 1.2 ad if (l->l_shlocks != 0)
616 1.2 ad panic("lockdebug_barrier: holding %d shared locks",
617 1.2 ad l->l_shlocks);
618 1.2 ad }
619 1.2 ad }
620 1.2 ad
621 1.2 ad /*
622 1.10 ad * lockdebug_mem_check:
623 1.10 ad *
624 1.10 ad * Check for in-use locks within a memory region that is
625 1.11.2.2 mjf * being freed.
626 1.10 ad */
627 1.10 ad void
628 1.10 ad lockdebug_mem_check(const char *func, void *base, size_t sz)
629 1.10 ad {
630 1.10 ad lockdebug_t *ld;
631 1.11.2.2 mjf lockdebuglk_t *lk;
632 1.11.2.2 mjf uintptr_t lock;
633 1.10 ad
634 1.11.2.2 mjf lockdebug_lock(&ld_tree_lk);
635 1.11.2.2 mjf ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base);
636 1.11.2.2 mjf lockdebug_unlock(&ld_tree_lk);
637 1.11.2.2 mjf if (ld == NULL)
638 1.11.2.2 mjf return;
639 1.11.2.2 mjf
640 1.11.2.2 mjf if ((ld->ld_flags & LD_SLEEPER) != 0)
641 1.11.2.2 mjf lk = &ld_sleeper_lk;
642 1.11.2.2 mjf else
643 1.11.2.2 mjf lk = &ld_spinner_lk;
644 1.10 ad
645 1.11.2.2 mjf lockdebug_lock(lk);
646 1.11.2.2 mjf lock = (uintptr_t)ld->ld_lock;
647 1.11.2.2 mjf if ((uintptr_t)base > lock)
648 1.11.2.2 mjf lockdebug_abort1(ld, lk, func, "corrupt tree", true);
649 1.11.2.2 mjf if (lock < (uintptr_t)base + sz) {
650 1.11.2.2 mjf lockdebug_abort1(ld, lk, func,
651 1.11.2.2 mjf "allocation contains active lock", !cold);
652 1.11.2.2 mjf return;
653 1.10 ad }
654 1.10 ad lockdebug_unlock(lk);
655 1.10 ad }
656 1.10 ad
657 1.10 ad /*
658 1.2 ad * lockdebug_dump:
659 1.2 ad *
660 1.2 ad * Dump information about a lock on panic, or for DDB.
661 1.2 ad */
662 1.2 ad static void
663 1.2 ad lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...))
664 1.2 ad {
665 1.2 ad int sleeper = (ld->ld_flags & LD_SLEEPER);
666 1.2 ad
667 1.2 ad (*pr)(
668 1.2 ad "lock address : %#018lx type : %18s\n"
669 1.2 ad "shared holds : %18u exclusive: %18u\n"
670 1.2 ad "shares wanted: %18u exclusive: %18u\n"
671 1.2 ad "current cpu : %18u last held: %18u\n"
672 1.2 ad "current lwp : %#018lx last held: %#018lx\n"
673 1.10 ad "last locked : %#018lx unlocked : %#018lx\n"
674 1.10 ad "initialized : %#018lx\n",
675 1.2 ad (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"),
676 1.2 ad (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0),
677 1.2 ad (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant,
678 1.2 ad (unsigned)cpu_number(), (unsigned)ld->ld_cpu,
679 1.2 ad (long)curlwp, (long)ld->ld_lwp,
680 1.10 ad (long)ld->ld_locked, (long)ld->ld_unlocked,
681 1.10 ad (long)ld->ld_initaddr);
682 1.2 ad
683 1.2 ad if (ld->ld_lockops->lo_dump != NULL)
684 1.2 ad (*ld->ld_lockops->lo_dump)(ld->ld_lock);
685 1.2 ad
686 1.2 ad if (sleeper) {
687 1.2 ad (*pr)("\n");
688 1.2 ad turnstile_print(ld->ld_lock, pr);
689 1.2 ad }
690 1.2 ad }
691 1.2 ad
692 1.2 ad /*
693 1.2 ad * lockdebug_dump:
694 1.2 ad *
695 1.2 ad * Dump information about a known lock.
696 1.2 ad */
697 1.5 ad static void
698 1.2 ad lockdebug_abort1(lockdebug_t *ld, lockdebuglk_t *lk, const char *func,
699 1.10 ad const char *msg, bool dopanic)
700 1.2 ad {
701 1.2 ad
702 1.2 ad printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name,
703 1.2 ad func, msg);
704 1.2 ad lockdebug_dump(ld, printf_nolog);
705 1.2 ad lockdebug_unlock(lk);
706 1.2 ad printf_nolog("\n");
707 1.10 ad if (dopanic)
708 1.10 ad panic("LOCKDEBUG");
709 1.2 ad }
710 1.2 ad
711 1.2 ad #endif /* LOCKDEBUG */
712 1.2 ad
713 1.2 ad /*
714 1.2 ad * lockdebug_lock_print:
715 1.2 ad *
716 1.2 ad * Handle the DDB 'show lock' command.
717 1.2 ad */
718 1.2 ad #ifdef DDB
719 1.2 ad void
720 1.2 ad lockdebug_lock_print(void *addr, void (*pr)(const char *, ...))
721 1.2 ad {
722 1.2 ad #ifdef LOCKDEBUG
723 1.2 ad lockdebug_t *ld;
724 1.2 ad
725 1.2 ad TAILQ_FOREACH(ld, &ld_all, ld_achain) {
726 1.2 ad if (ld->ld_lock == addr) {
727 1.2 ad lockdebug_dump(ld, pr);
728 1.2 ad return;
729 1.2 ad }
730 1.2 ad }
731 1.2 ad (*pr)("Sorry, no record of a lock with address %p found.\n", addr);
732 1.2 ad #else
733 1.2 ad (*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n");
734 1.2 ad #endif /* LOCKDEBUG */
735 1.2 ad }
736 1.2 ad #endif /* DDB */
737 1.2 ad
738 1.2 ad /*
739 1.2 ad * lockdebug_abort:
740 1.2 ad *
741 1.2 ad * An error has been trapped - dump lock info and call panic().
742 1.2 ad */
743 1.2 ad void
744 1.11.2.2 mjf lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func,
745 1.11.2.2 mjf const char *msg)
746 1.2 ad {
747 1.2 ad #ifdef LOCKDEBUG
748 1.2 ad lockdebug_t *ld;
749 1.2 ad lockdebuglk_t *lk;
750 1.2 ad
751 1.11.2.2 mjf if ((ld = lockdebug_lookup(lock, &lk)) != NULL) {
752 1.10 ad lockdebug_abort1(ld, lk, func, msg, true);
753 1.2 ad /* NOTREACHED */
754 1.2 ad }
755 1.2 ad #endif /* LOCKDEBUG */
756 1.2 ad
757 1.2 ad printf_nolog("%s error: %s: %s\n\n"
758 1.2 ad "lock address : %#018lx\n"
759 1.2 ad "current cpu : %18d\n"
760 1.2 ad "current lwp : %#018lx\n",
761 1.2 ad ops->lo_name, func, msg, (long)lock, (int)cpu_number(),
762 1.2 ad (long)curlwp);
763 1.2 ad
764 1.2 ad (*ops->lo_dump)(lock);
765 1.2 ad
766 1.2 ad printf_nolog("\n");
767 1.2 ad panic("lock error");
768 1.2 ad }
769