subr_lockdebug.c revision 1.4.2.6 1 1.4.2.6 yamt /* $NetBSD: subr_lockdebug.c,v 1.4.2.6 2007/12/07 17:33:06 yamt Exp $ */
2 1.4.2.2 yamt
3 1.4.2.2 yamt /*-
4 1.4.2.2 yamt * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc.
5 1.4.2.2 yamt * All rights reserved.
6 1.4.2.2 yamt *
7 1.4.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation
8 1.4.2.2 yamt * by Andrew Doran.
9 1.4.2.2 yamt *
10 1.4.2.2 yamt * Redistribution and use in source and binary forms, with or without
11 1.4.2.2 yamt * modification, are permitted provided that the following conditions
12 1.4.2.2 yamt * are met:
13 1.4.2.2 yamt * 1. Redistributions of source code must retain the above copyright
14 1.4.2.2 yamt * notice, this list of conditions and the following disclaimer.
15 1.4.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright
16 1.4.2.2 yamt * notice, this list of conditions and the following disclaimer in the
17 1.4.2.2 yamt * documentation and/or other materials provided with the distribution.
18 1.4.2.2 yamt * 3. All advertising materials mentioning features or use of this software
19 1.4.2.2 yamt * must display the following acknowledgement:
20 1.4.2.2 yamt * This product includes software developed by the NetBSD
21 1.4.2.2 yamt * Foundation, Inc. and its contributors.
22 1.4.2.2 yamt * 4. Neither the name of The NetBSD Foundation nor the names of its
23 1.4.2.2 yamt * contributors may be used to endorse or promote products derived
24 1.4.2.2 yamt * from this software without specific prior written permission.
25 1.4.2.2 yamt *
26 1.4.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 1.4.2.2 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 1.4.2.2 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 1.4.2.2 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 1.4.2.2 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 1.4.2.2 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 1.4.2.2 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 1.4.2.2 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 1.4.2.2 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 1.4.2.2 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 1.4.2.2 yamt * POSSIBILITY OF SUCH DAMAGE.
37 1.4.2.2 yamt */
38 1.4.2.2 yamt
39 1.4.2.2 yamt /*
40 1.4.2.4 yamt * Basic lock debugging code shared among lock primitives.
41 1.4.2.2 yamt */
42 1.4.2.2 yamt
43 1.4.2.4 yamt #include <sys/cdefs.h>
44 1.4.2.6 yamt __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.4.2.6 2007/12/07 17:33:06 yamt Exp $");
45 1.4.2.4 yamt
46 1.4.2.2 yamt #include "opt_multiprocessor.h"
47 1.4.2.2 yamt #include "opt_ddb.h"
48 1.4.2.2 yamt
49 1.4.2.2 yamt #include <sys/param.h>
50 1.4.2.2 yamt #include <sys/proc.h>
51 1.4.2.2 yamt #include <sys/systm.h>
52 1.4.2.4 yamt #include <sys/kernel.h>
53 1.4.2.2 yamt #include <sys/kmem.h>
54 1.4.2.2 yamt #include <sys/lock.h>
55 1.4.2.2 yamt #include <sys/lockdebug.h>
56 1.4.2.2 yamt #include <sys/sleepq.h>
57 1.4.2.4 yamt #include <sys/cpu.h>
58 1.4.2.6 yamt #include <sys/atomic.h>
59 1.4.2.6 yamt
60 1.4.2.6 yamt #include <lib/libkern/rb.h>
61 1.4.2.2 yamt
62 1.4.2.2 yamt #ifdef LOCKDEBUG
63 1.4.2.2 yamt
64 1.4.2.2 yamt #define LD_BATCH_SHIFT 9
65 1.4.2.2 yamt #define LD_BATCH (1 << LD_BATCH_SHIFT)
66 1.4.2.2 yamt #define LD_BATCH_MASK (LD_BATCH - 1)
67 1.4.2.2 yamt #define LD_MAX_LOCKS 1048576
68 1.4.2.2 yamt #define LD_SLOP 16
69 1.4.2.2 yamt
70 1.4.2.2 yamt #define LD_LOCKED 0x01
71 1.4.2.2 yamt #define LD_SLEEPER 0x02
72 1.4.2.2 yamt
73 1.4.2.2 yamt typedef union lockdebuglk {
74 1.4.2.2 yamt struct {
75 1.4.2.2 yamt __cpu_simple_lock_t lku_lock;
76 1.4.2.2 yamt int lku_oldspl;
77 1.4.2.2 yamt } ul;
78 1.4.2.2 yamt uint8_t lk_pad[64];
79 1.4.2.2 yamt } volatile __aligned(64) lockdebuglk_t;
80 1.4.2.2 yamt
81 1.4.2.2 yamt #define lk_lock ul.lku_lock
82 1.4.2.2 yamt #define lk_oldspl ul.lku_oldspl
83 1.4.2.2 yamt
84 1.4.2.2 yamt typedef struct lockdebug {
85 1.4.2.6 yamt struct rb_node ld_rb_node; /* must be the first member */
86 1.4.2.2 yamt _TAILQ_ENTRY(struct lockdebug, volatile) ld_chain;
87 1.4.2.2 yamt _TAILQ_ENTRY(struct lockdebug, volatile) ld_achain;
88 1.4.2.2 yamt volatile void *ld_lock;
89 1.4.2.2 yamt lockops_t *ld_lockops;
90 1.4.2.2 yamt struct lwp *ld_lwp;
91 1.4.2.2 yamt uintptr_t ld_locked;
92 1.4.2.2 yamt uintptr_t ld_unlocked;
93 1.4.2.4 yamt uintptr_t ld_initaddr;
94 1.4.2.2 yamt uint16_t ld_shares;
95 1.4.2.2 yamt uint16_t ld_cpu;
96 1.4.2.2 yamt uint8_t ld_flags;
97 1.4.2.2 yamt uint8_t ld_shwant; /* advisory */
98 1.4.2.2 yamt uint8_t ld_exwant; /* advisory */
99 1.4.2.2 yamt uint8_t ld_unused;
100 1.4.2.2 yamt } volatile lockdebug_t;
101 1.4.2.2 yamt
102 1.4.2.2 yamt typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t;
103 1.4.2.2 yamt
104 1.4.2.6 yamt lockdebuglk_t ld_tree_lk;
105 1.4.2.2 yamt lockdebuglk_t ld_sleeper_lk;
106 1.4.2.2 yamt lockdebuglk_t ld_spinner_lk;
107 1.4.2.2 yamt lockdebuglk_t ld_free_lk;
108 1.4.2.2 yamt
109 1.4.2.5 yamt lockdebuglist_t ld_sleepers = TAILQ_HEAD_INITIALIZER(ld_sleepers);
110 1.4.2.5 yamt lockdebuglist_t ld_spinners = TAILQ_HEAD_INITIALIZER(ld_spinners);
111 1.4.2.5 yamt lockdebuglist_t ld_free = TAILQ_HEAD_INITIALIZER(ld_free);
112 1.4.2.5 yamt lockdebuglist_t ld_all = TAILQ_HEAD_INITIALIZER(ld_all);
113 1.4.2.2 yamt int ld_nfree;
114 1.4.2.2 yamt int ld_freeptr;
115 1.4.2.2 yamt int ld_recurse;
116 1.4.2.3 yamt bool ld_nomore;
117 1.4.2.2 yamt lockdebug_t *ld_table[LD_MAX_LOCKS / LD_BATCH];
118 1.4.2.2 yamt
119 1.4.2.2 yamt lockdebug_t ld_prime[LD_BATCH];
120 1.4.2.2 yamt
121 1.4.2.3 yamt static void lockdebug_abort1(lockdebug_t *, lockdebuglk_t *lk,
122 1.4.2.4 yamt const char *, const char *, bool);
123 1.4.2.3 yamt static void lockdebug_more(void);
124 1.4.2.3 yamt static void lockdebug_init(void);
125 1.4.2.2 yamt
126 1.4.2.6 yamt static signed int
127 1.4.2.6 yamt ld_rb_compare_nodes(const struct rb_node *n1, const struct rb_node *n2)
128 1.4.2.6 yamt {
129 1.4.2.6 yamt const lockdebug_t *ld1 = (const void *)n1;
130 1.4.2.6 yamt const lockdebug_t *ld2 = (const void *)n2;
131 1.4.2.6 yamt const uintptr_t a = (uintptr_t)ld1->ld_lock;
132 1.4.2.6 yamt const uintptr_t b = (uintptr_t)ld2->ld_lock;
133 1.4.2.6 yamt
134 1.4.2.6 yamt if (a < b)
135 1.4.2.6 yamt return 1;
136 1.4.2.6 yamt if (a > b)
137 1.4.2.6 yamt return -1;
138 1.4.2.6 yamt return 0;
139 1.4.2.6 yamt }
140 1.4.2.6 yamt
141 1.4.2.6 yamt static signed int
142 1.4.2.6 yamt ld_rb_compare_key(const struct rb_node *n, const void *key)
143 1.4.2.6 yamt {
144 1.4.2.6 yamt const lockdebug_t *ld = (const void *)n;
145 1.4.2.6 yamt const uintptr_t a = (uintptr_t)ld->ld_lock;
146 1.4.2.6 yamt const uintptr_t b = (uintptr_t)key;
147 1.4.2.6 yamt
148 1.4.2.6 yamt if (a < b)
149 1.4.2.6 yamt return 1;
150 1.4.2.6 yamt if (a > b)
151 1.4.2.6 yamt return -1;
152 1.4.2.6 yamt return 0;
153 1.4.2.6 yamt }
154 1.4.2.6 yamt
155 1.4.2.6 yamt static struct rb_tree ld_rb_tree;
156 1.4.2.6 yamt
157 1.4.2.6 yamt static const struct rb_tree_ops ld_rb_tree_ops = {
158 1.4.2.6 yamt .rb_compare_nodes = ld_rb_compare_nodes,
159 1.4.2.6 yamt .rb_compare_key = ld_rb_compare_key,
160 1.4.2.6 yamt };
161 1.4.2.6 yamt
162 1.4.2.2 yamt static inline void
163 1.4.2.2 yamt lockdebug_lock(lockdebuglk_t *lk)
164 1.4.2.2 yamt {
165 1.4.2.2 yamt int s;
166 1.4.2.2 yamt
167 1.4.2.3 yamt s = splhigh();
168 1.4.2.2 yamt __cpu_simple_lock(&lk->lk_lock);
169 1.4.2.2 yamt lk->lk_oldspl = s;
170 1.4.2.2 yamt }
171 1.4.2.2 yamt
172 1.4.2.2 yamt static inline void
173 1.4.2.2 yamt lockdebug_unlock(lockdebuglk_t *lk)
174 1.4.2.2 yamt {
175 1.4.2.2 yamt int s;
176 1.4.2.2 yamt
177 1.4.2.2 yamt s = lk->lk_oldspl;
178 1.4.2.2 yamt __cpu_simple_unlock(&(lk->lk_lock));
179 1.4.2.2 yamt splx(s);
180 1.4.2.2 yamt }
181 1.4.2.2 yamt
182 1.4.2.6 yamt static inline lockdebug_t *
183 1.4.2.6 yamt lockdebug_lookup1(volatile void *lock, lockdebuglk_t **lk)
184 1.4.2.4 yamt {
185 1.4.2.6 yamt lockdebug_t *ld;
186 1.4.2.6 yamt
187 1.4.2.6 yamt lockdebug_lock(&ld_tree_lk);
188 1.4.2.6 yamt ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock));
189 1.4.2.6 yamt lockdebug_unlock(&ld_tree_lk);
190 1.4.2.6 yamt if (ld == NULL)
191 1.4.2.6 yamt return NULL;
192 1.4.2.6 yamt
193 1.4.2.6 yamt if ((ld->ld_flags & LD_SLEEPER) != 0)
194 1.4.2.6 yamt *lk = &ld_sleeper_lk;
195 1.4.2.6 yamt else
196 1.4.2.6 yamt *lk = &ld_spinner_lk;
197 1.4.2.4 yamt
198 1.4.2.4 yamt lockdebug_lock(*lk);
199 1.4.2.6 yamt return ld;
200 1.4.2.4 yamt }
201 1.4.2.4 yamt
202 1.4.2.2 yamt /*
203 1.4.2.2 yamt * lockdebug_lookup:
204 1.4.2.2 yamt *
205 1.4.2.6 yamt * Find a lockdebug structure by a pointer to a lock and return it locked.
206 1.4.2.2 yamt */
207 1.4.2.2 yamt static inline lockdebug_t *
208 1.4.2.6 yamt lockdebug_lookup(volatile void *lock, lockdebuglk_t **lk)
209 1.4.2.2 yamt {
210 1.4.2.6 yamt lockdebug_t *ld;
211 1.4.2.2 yamt
212 1.4.2.6 yamt ld = lockdebug_lookup1(lock, lk);
213 1.4.2.6 yamt if (ld == NULL)
214 1.4.2.6 yamt panic("lockdebug_lookup: uninitialized lock (lock=%p)", lock);
215 1.4.2.2 yamt return ld;
216 1.4.2.2 yamt }
217 1.4.2.2 yamt
218 1.4.2.2 yamt /*
219 1.4.2.2 yamt * lockdebug_init:
220 1.4.2.2 yamt *
221 1.4.2.2 yamt * Initialize the lockdebug system. Allocate an initial pool of
222 1.4.2.2 yamt * lockdebug structures before the VM system is up and running.
223 1.4.2.2 yamt */
224 1.4.2.3 yamt static void
225 1.4.2.2 yamt lockdebug_init(void)
226 1.4.2.2 yamt {
227 1.4.2.2 yamt lockdebug_t *ld;
228 1.4.2.2 yamt int i;
229 1.4.2.2 yamt
230 1.4.2.6 yamt __cpu_simple_lock_init(&ld_tree_lk.lk_lock);
231 1.4.2.2 yamt __cpu_simple_lock_init(&ld_sleeper_lk.lk_lock);
232 1.4.2.2 yamt __cpu_simple_lock_init(&ld_spinner_lk.lk_lock);
233 1.4.2.2 yamt __cpu_simple_lock_init(&ld_free_lk.lk_lock);
234 1.4.2.2 yamt
235 1.4.2.6 yamt rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops);
236 1.4.2.6 yamt
237 1.4.2.2 yamt ld = ld_prime;
238 1.4.2.2 yamt ld_table[0] = ld;
239 1.4.2.2 yamt for (i = 1, ld++; i < LD_BATCH; i++, ld++) {
240 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
241 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
242 1.4.2.2 yamt }
243 1.4.2.2 yamt ld_freeptr = 1;
244 1.4.2.2 yamt ld_nfree = LD_BATCH - 1;
245 1.4.2.2 yamt }
246 1.4.2.2 yamt
247 1.4.2.2 yamt /*
248 1.4.2.2 yamt * lockdebug_alloc:
249 1.4.2.2 yamt *
250 1.4.2.2 yamt * A lock is being initialized, so allocate an associated debug
251 1.4.2.2 yamt * structure.
252 1.4.2.2 yamt */
253 1.4.2.6 yamt bool
254 1.4.2.4 yamt lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr)
255 1.4.2.2 yamt {
256 1.4.2.2 yamt struct cpu_info *ci;
257 1.4.2.2 yamt lockdebug_t *ld;
258 1.4.2.6 yamt lockdebuglk_t *lk;
259 1.4.2.2 yamt
260 1.4.2.3 yamt if (lo == NULL || panicstr != NULL)
261 1.4.2.6 yamt return false;
262 1.4.2.3 yamt if (ld_freeptr == 0)
263 1.4.2.3 yamt lockdebug_init();
264 1.4.2.2 yamt
265 1.4.2.6 yamt if ((ld = lockdebug_lookup1(lock, &lk)) != NULL) {
266 1.4.2.6 yamt lockdebug_abort1(ld, lk, __func__, "already initialized", true);
267 1.4.2.6 yamt /* NOTREACHED */
268 1.4.2.6 yamt }
269 1.4.2.6 yamt
270 1.4.2.2 yamt ci = curcpu();
271 1.4.2.2 yamt
272 1.4.2.2 yamt /*
273 1.4.2.2 yamt * Pinch a new debug structure. We may recurse because we call
274 1.4.2.2 yamt * kmem_alloc(), which may need to initialize new locks somewhere
275 1.4.2.3 yamt * down the path. If not recursing, we try to maintain at least
276 1.4.2.2 yamt * LD_SLOP structures free, which should hopefully be enough to
277 1.4.2.2 yamt * satisfy kmem_alloc(). If we can't provide a structure, not to
278 1.4.2.2 yamt * worry: we'll just mark the lock as not having an ID.
279 1.4.2.2 yamt */
280 1.4.2.2 yamt lockdebug_lock(&ld_free_lk);
281 1.4.2.2 yamt ci->ci_lkdebug_recurse++;
282 1.4.2.2 yamt
283 1.4.2.2 yamt if (TAILQ_EMPTY(&ld_free)) {
284 1.4.2.3 yamt if (ci->ci_lkdebug_recurse > 1 || ld_nomore) {
285 1.4.2.2 yamt ci->ci_lkdebug_recurse--;
286 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk);
287 1.4.2.6 yamt return false;
288 1.4.2.2 yamt }
289 1.4.2.2 yamt lockdebug_more();
290 1.4.2.2 yamt } else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP)
291 1.4.2.2 yamt lockdebug_more();
292 1.4.2.2 yamt
293 1.4.2.2 yamt if ((ld = TAILQ_FIRST(&ld_free)) == NULL) {
294 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk);
295 1.4.2.6 yamt return false;
296 1.4.2.2 yamt }
297 1.4.2.2 yamt
298 1.4.2.2 yamt TAILQ_REMOVE(&ld_free, ld, ld_chain);
299 1.4.2.2 yamt ld_nfree--;
300 1.4.2.2 yamt
301 1.4.2.2 yamt ci->ci_lkdebug_recurse--;
302 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk);
303 1.4.2.2 yamt
304 1.4.2.2 yamt if (ld->ld_lock != NULL)
305 1.4.2.2 yamt panic("lockdebug_alloc: corrupt table");
306 1.4.2.2 yamt
307 1.4.2.2 yamt if (lo->lo_sleeplock)
308 1.4.2.2 yamt lockdebug_lock(&ld_sleeper_lk);
309 1.4.2.2 yamt else
310 1.4.2.2 yamt lockdebug_lock(&ld_spinner_lk);
311 1.4.2.2 yamt
312 1.4.2.2 yamt /* Initialise the structure. */
313 1.4.2.2 yamt ld->ld_lock = lock;
314 1.4.2.2 yamt ld->ld_lockops = lo;
315 1.4.2.2 yamt ld->ld_locked = 0;
316 1.4.2.2 yamt ld->ld_unlocked = 0;
317 1.4.2.2 yamt ld->ld_lwp = NULL;
318 1.4.2.4 yamt ld->ld_initaddr = initaddr;
319 1.4.2.2 yamt
320 1.4.2.6 yamt lockdebug_lock(&ld_tree_lk);
321 1.4.2.6 yamt rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
322 1.4.2.6 yamt lockdebug_unlock(&ld_tree_lk);
323 1.4.2.6 yamt
324 1.4.2.2 yamt if (lo->lo_sleeplock) {
325 1.4.2.2 yamt ld->ld_flags = LD_SLEEPER;
326 1.4.2.2 yamt lockdebug_unlock(&ld_sleeper_lk);
327 1.4.2.2 yamt } else {
328 1.4.2.2 yamt ld->ld_flags = 0;
329 1.4.2.2 yamt lockdebug_unlock(&ld_spinner_lk);
330 1.4.2.2 yamt }
331 1.4.2.2 yamt
332 1.4.2.6 yamt return true;
333 1.4.2.2 yamt }
334 1.4.2.2 yamt
335 1.4.2.2 yamt /*
336 1.4.2.2 yamt * lockdebug_free:
337 1.4.2.2 yamt *
338 1.4.2.2 yamt * A lock is being destroyed, so release debugging resources.
339 1.4.2.2 yamt */
340 1.4.2.2 yamt void
341 1.4.2.6 yamt lockdebug_free(volatile void *lock)
342 1.4.2.2 yamt {
343 1.4.2.2 yamt lockdebug_t *ld;
344 1.4.2.2 yamt lockdebuglk_t *lk;
345 1.4.2.2 yamt
346 1.4.2.2 yamt if (panicstr != NULL)
347 1.4.2.2 yamt return;
348 1.4.2.2 yamt
349 1.4.2.6 yamt ld = lockdebug_lookup(lock, &lk);
350 1.4.2.6 yamt if (ld == NULL) {
351 1.4.2.2 yamt panic("lockdebug_free: destroying uninitialized lock %p"
352 1.4.2.6 yamt "(ld_lock=%p)", lock, ld->ld_lock);
353 1.4.2.4 yamt lockdebug_abort1(ld, lk, __func__, "lock record follows",
354 1.4.2.4 yamt true);
355 1.4.2.2 yamt }
356 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0)
357 1.4.2.4 yamt lockdebug_abort1(ld, lk, __func__, "is locked", true);
358 1.4.2.6 yamt lockdebug_lock(&ld_tree_lk);
359 1.4.2.6 yamt rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(&ld->ld_rb_node));
360 1.4.2.6 yamt lockdebug_unlock(&ld_tree_lk);
361 1.4.2.2 yamt ld->ld_lock = NULL;
362 1.4.2.2 yamt lockdebug_unlock(lk);
363 1.4.2.2 yamt
364 1.4.2.2 yamt lockdebug_lock(&ld_free_lk);
365 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
366 1.4.2.2 yamt ld_nfree++;
367 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk);
368 1.4.2.2 yamt }
369 1.4.2.2 yamt
370 1.4.2.2 yamt /*
371 1.4.2.2 yamt * lockdebug_more:
372 1.4.2.2 yamt *
373 1.4.2.2 yamt * Allocate a batch of debug structures and add to the free list.
374 1.4.2.2 yamt * Must be called with ld_free_lk held.
375 1.4.2.2 yamt */
376 1.4.2.3 yamt static void
377 1.4.2.2 yamt lockdebug_more(void)
378 1.4.2.2 yamt {
379 1.4.2.2 yamt lockdebug_t *ld;
380 1.4.2.2 yamt void *block;
381 1.4.2.3 yamt int i, base, m;
382 1.4.2.2 yamt
383 1.4.2.2 yamt while (ld_nfree < LD_SLOP) {
384 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk);
385 1.4.2.2 yamt block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP);
386 1.4.2.2 yamt lockdebug_lock(&ld_free_lk);
387 1.4.2.2 yamt
388 1.4.2.2 yamt if (block == NULL)
389 1.4.2.2 yamt return;
390 1.4.2.2 yamt
391 1.4.2.2 yamt if (ld_nfree > LD_SLOP) {
392 1.4.2.2 yamt /* Somebody beat us to it. */
393 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk);
394 1.4.2.2 yamt kmem_free(block, LD_BATCH * sizeof(lockdebug_t));
395 1.4.2.2 yamt lockdebug_lock(&ld_free_lk);
396 1.4.2.2 yamt continue;
397 1.4.2.2 yamt }
398 1.4.2.2 yamt
399 1.4.2.2 yamt base = ld_freeptr;
400 1.4.2.2 yamt ld_nfree += LD_BATCH;
401 1.4.2.2 yamt ld = block;
402 1.4.2.2 yamt base <<= LD_BATCH_SHIFT;
403 1.4.2.3 yamt m = min(LD_MAX_LOCKS, base + LD_BATCH);
404 1.4.2.3 yamt
405 1.4.2.3 yamt if (m == LD_MAX_LOCKS)
406 1.4.2.3 yamt ld_nomore = true;
407 1.4.2.2 yamt
408 1.4.2.3 yamt for (i = base; i < m; i++, ld++) {
409 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain);
410 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain);
411 1.4.2.2 yamt }
412 1.4.2.2 yamt
413 1.4.2.6 yamt membar_producer();
414 1.4.2.2 yamt ld_table[ld_freeptr++] = block;
415 1.4.2.2 yamt }
416 1.4.2.2 yamt }
417 1.4.2.2 yamt
418 1.4.2.2 yamt /*
419 1.4.2.2 yamt * lockdebug_wantlock:
420 1.4.2.2 yamt *
421 1.4.2.2 yamt * Process the preamble to a lock acquire.
422 1.4.2.2 yamt */
423 1.4.2.2 yamt void
424 1.4.2.6 yamt lockdebug_wantlock(volatile void *lock, uintptr_t where, int shared)
425 1.4.2.2 yamt {
426 1.4.2.2 yamt struct lwp *l = curlwp;
427 1.4.2.2 yamt lockdebuglk_t *lk;
428 1.4.2.2 yamt lockdebug_t *ld;
429 1.4.2.2 yamt bool recurse;
430 1.4.2.2 yamt
431 1.4.2.2 yamt (void)shared;
432 1.4.2.2 yamt recurse = false;
433 1.4.2.2 yamt
434 1.4.2.2 yamt if (panicstr != NULL)
435 1.4.2.2 yamt return;
436 1.4.2.2 yamt
437 1.4.2.6 yamt if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
438 1.4.2.2 yamt return;
439 1.4.2.2 yamt
440 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) != 0) {
441 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) {
442 1.4.2.2 yamt if (ld->ld_lwp == l)
443 1.4.2.2 yamt recurse = true;
444 1.4.2.2 yamt } else if (ld->ld_cpu == (uint16_t)cpu_number())
445 1.4.2.2 yamt recurse = true;
446 1.4.2.2 yamt }
447 1.4.2.2 yamt
448 1.4.2.4 yamt #ifdef notyet
449 1.4.2.4 yamt if (cpu_intr_p()) {
450 1.4.2.4 yamt if ((ld->ld_flags & LD_SLEEPER) != 0)
451 1.4.2.4 yamt lockdebug_abort1(ld, lk, __func__,
452 1.4.2.4 yamt "acquiring sleep lock from interrupt context",
453 1.4.2.4 yamt true);
454 1.4.2.4 yamt }
455 1.4.2.4 yamt #endif
456 1.4.2.4 yamt
457 1.4.2.2 yamt if (shared)
458 1.4.2.2 yamt ld->ld_shwant++;
459 1.4.2.2 yamt else
460 1.4.2.2 yamt ld->ld_exwant++;
461 1.4.2.2 yamt
462 1.4.2.2 yamt if (recurse)
463 1.4.2.4 yamt lockdebug_abort1(ld, lk, __func__, "locking against myself",
464 1.4.2.4 yamt true);
465 1.4.2.2 yamt
466 1.4.2.2 yamt lockdebug_unlock(lk);
467 1.4.2.2 yamt }
468 1.4.2.2 yamt
469 1.4.2.2 yamt /*
470 1.4.2.2 yamt * lockdebug_locked:
471 1.4.2.2 yamt *
472 1.4.2.2 yamt * Process a lock acquire operation.
473 1.4.2.2 yamt */
474 1.4.2.2 yamt void
475 1.4.2.6 yamt lockdebug_locked(volatile void *lock, uintptr_t where, int shared)
476 1.4.2.2 yamt {
477 1.4.2.2 yamt struct lwp *l = curlwp;
478 1.4.2.2 yamt lockdebuglk_t *lk;
479 1.4.2.2 yamt lockdebug_t *ld;
480 1.4.2.2 yamt
481 1.4.2.2 yamt if (panicstr != NULL)
482 1.4.2.2 yamt return;
483 1.4.2.2 yamt
484 1.4.2.6 yamt if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
485 1.4.2.2 yamt return;
486 1.4.2.2 yamt
487 1.4.2.2 yamt if (shared) {
488 1.4.2.2 yamt l->l_shlocks++;
489 1.4.2.2 yamt ld->ld_shares++;
490 1.4.2.2 yamt ld->ld_shwant--;
491 1.4.2.2 yamt } else {
492 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) != 0)
493 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__,
494 1.4.2.4 yamt "already locked", true);
495 1.4.2.2 yamt
496 1.4.2.2 yamt ld->ld_flags |= LD_LOCKED;
497 1.4.2.2 yamt ld->ld_locked = where;
498 1.4.2.2 yamt ld->ld_cpu = (uint16_t)cpu_number();
499 1.4.2.2 yamt ld->ld_lwp = l;
500 1.4.2.2 yamt ld->ld_exwant--;
501 1.4.2.2 yamt
502 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) {
503 1.4.2.2 yamt l->l_exlocks++;
504 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_sleepers, ld, ld_chain);
505 1.4.2.2 yamt } else {
506 1.4.2.2 yamt curcpu()->ci_spin_locks2++;
507 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_spinners, ld, ld_chain);
508 1.4.2.2 yamt }
509 1.4.2.2 yamt }
510 1.4.2.2 yamt
511 1.4.2.2 yamt lockdebug_unlock(lk);
512 1.4.2.2 yamt }
513 1.4.2.2 yamt
514 1.4.2.2 yamt /*
515 1.4.2.2 yamt * lockdebug_unlocked:
516 1.4.2.2 yamt *
517 1.4.2.2 yamt * Process a lock release operation.
518 1.4.2.2 yamt */
519 1.4.2.2 yamt void
520 1.4.2.6 yamt lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared)
521 1.4.2.2 yamt {
522 1.4.2.2 yamt struct lwp *l = curlwp;
523 1.4.2.2 yamt lockdebuglk_t *lk;
524 1.4.2.2 yamt lockdebug_t *ld;
525 1.4.2.2 yamt
526 1.4.2.2 yamt if (panicstr != NULL)
527 1.4.2.2 yamt return;
528 1.4.2.2 yamt
529 1.4.2.6 yamt if ((ld = lockdebug_lookup(lock, &lk)) == NULL)
530 1.4.2.2 yamt return;
531 1.4.2.2 yamt
532 1.4.2.2 yamt if (shared) {
533 1.4.2.2 yamt if (l->l_shlocks == 0)
534 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__,
535 1.4.2.4 yamt "no shared locks held by LWP", true);
536 1.4.2.2 yamt if (ld->ld_shares == 0)
537 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__,
538 1.4.2.4 yamt "no shared holds on this lock", true);
539 1.4.2.2 yamt l->l_shlocks--;
540 1.4.2.2 yamt ld->ld_shares--;
541 1.4.2.2 yamt } else {
542 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) == 0)
543 1.4.2.4 yamt lockdebug_abort1(ld, lk, __func__, "not locked",
544 1.4.2.4 yamt true);
545 1.4.2.2 yamt
546 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) {
547 1.4.2.2 yamt if (ld->ld_lwp != curlwp)
548 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__,
549 1.4.2.4 yamt "not held by current LWP", true);
550 1.4.2.2 yamt ld->ld_flags &= ~LD_LOCKED;
551 1.4.2.2 yamt ld->ld_unlocked = where;
552 1.4.2.2 yamt ld->ld_lwp = NULL;
553 1.4.2.2 yamt curlwp->l_exlocks--;
554 1.4.2.2 yamt TAILQ_REMOVE(&ld_sleepers, ld, ld_chain);
555 1.4.2.2 yamt } else {
556 1.4.2.2 yamt if (ld->ld_cpu != (uint16_t)cpu_number())
557 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__,
558 1.4.2.4 yamt "not held by current CPU", true);
559 1.4.2.2 yamt ld->ld_flags &= ~LD_LOCKED;
560 1.4.2.2 yamt ld->ld_unlocked = where;
561 1.4.2.2 yamt ld->ld_lwp = NULL;
562 1.4.2.2 yamt curcpu()->ci_spin_locks2--;
563 1.4.2.2 yamt TAILQ_REMOVE(&ld_spinners, ld, ld_chain);
564 1.4.2.2 yamt }
565 1.4.2.2 yamt }
566 1.4.2.2 yamt
567 1.4.2.2 yamt lockdebug_unlock(lk);
568 1.4.2.2 yamt }
569 1.4.2.2 yamt
570 1.4.2.2 yamt /*
571 1.4.2.2 yamt * lockdebug_barrier:
572 1.4.2.2 yamt *
573 1.4.2.2 yamt * Panic if we hold more than one specified spin lock, and optionally,
574 1.4.2.2 yamt * if we hold sleep locks.
575 1.4.2.2 yamt */
576 1.4.2.2 yamt void
577 1.4.2.2 yamt lockdebug_barrier(volatile void *spinlock, int slplocks)
578 1.4.2.2 yamt {
579 1.4.2.2 yamt struct lwp *l = curlwp;
580 1.4.2.2 yamt lockdebug_t *ld;
581 1.4.2.2 yamt uint16_t cpuno;
582 1.4.2.2 yamt
583 1.4.2.2 yamt if (panicstr != NULL)
584 1.4.2.2 yamt return;
585 1.4.2.2 yamt
586 1.4.2.2 yamt if (curcpu()->ci_spin_locks2 != 0) {
587 1.4.2.2 yamt cpuno = (uint16_t)cpu_number();
588 1.4.2.2 yamt
589 1.4.2.2 yamt lockdebug_lock(&ld_spinner_lk);
590 1.4.2.2 yamt TAILQ_FOREACH(ld, &ld_spinners, ld_chain) {
591 1.4.2.2 yamt if (ld->ld_lock == spinlock) {
592 1.4.2.2 yamt if (ld->ld_cpu != cpuno)
593 1.4.2.2 yamt lockdebug_abort1(ld, &ld_spinner_lk,
594 1.4.2.2 yamt __func__,
595 1.4.2.4 yamt "not held by current CPU", true);
596 1.4.2.2 yamt continue;
597 1.4.2.2 yamt }
598 1.4.2.5 yamt if (ld->ld_cpu == cpuno && (l->l_pflag & LP_INTR) == 0)
599 1.4.2.2 yamt lockdebug_abort1(ld, &ld_spinner_lk,
600 1.4.2.4 yamt __func__, "spin lock held", true);
601 1.4.2.2 yamt }
602 1.4.2.2 yamt lockdebug_unlock(&ld_spinner_lk);
603 1.4.2.2 yamt }
604 1.4.2.2 yamt
605 1.4.2.2 yamt if (!slplocks) {
606 1.4.2.2 yamt if (l->l_exlocks != 0) {
607 1.4.2.2 yamt lockdebug_lock(&ld_sleeper_lk);
608 1.4.2.2 yamt TAILQ_FOREACH(ld, &ld_sleepers, ld_chain) {
609 1.4.2.2 yamt if (ld->ld_lwp == l)
610 1.4.2.2 yamt lockdebug_abort1(ld, &ld_sleeper_lk,
611 1.4.2.4 yamt __func__, "sleep lock held", true);
612 1.4.2.2 yamt }
613 1.4.2.2 yamt lockdebug_unlock(&ld_sleeper_lk);
614 1.4.2.2 yamt }
615 1.4.2.2 yamt if (l->l_shlocks != 0)
616 1.4.2.2 yamt panic("lockdebug_barrier: holding %d shared locks",
617 1.4.2.2 yamt l->l_shlocks);
618 1.4.2.2 yamt }
619 1.4.2.2 yamt }
620 1.4.2.2 yamt
621 1.4.2.2 yamt /*
622 1.4.2.4 yamt * lockdebug_mem_check:
623 1.4.2.4 yamt *
624 1.4.2.4 yamt * Check for in-use locks within a memory region that is
625 1.4.2.6 yamt * being freed.
626 1.4.2.4 yamt */
627 1.4.2.4 yamt void
628 1.4.2.4 yamt lockdebug_mem_check(const char *func, void *base, size_t sz)
629 1.4.2.4 yamt {
630 1.4.2.4 yamt lockdebug_t *ld;
631 1.4.2.6 yamt lockdebuglk_t *lk;
632 1.4.2.6 yamt uintptr_t lock;
633 1.4.2.4 yamt
634 1.4.2.6 yamt lockdebug_lock(&ld_tree_lk);
635 1.4.2.6 yamt ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base);
636 1.4.2.6 yamt lockdebug_unlock(&ld_tree_lk);
637 1.4.2.6 yamt if (ld == NULL)
638 1.4.2.6 yamt return;
639 1.4.2.6 yamt
640 1.4.2.6 yamt if ((ld->ld_flags & LD_SLEEPER) != 0)
641 1.4.2.6 yamt lk = &ld_sleeper_lk;
642 1.4.2.6 yamt else
643 1.4.2.6 yamt lk = &ld_spinner_lk;
644 1.4.2.4 yamt
645 1.4.2.6 yamt lockdebug_lock(lk);
646 1.4.2.6 yamt lock = (uintptr_t)ld->ld_lock;
647 1.4.2.6 yamt if ((uintptr_t)base > lock)
648 1.4.2.6 yamt lockdebug_abort1(ld, lk, func, "corrupt tree", true);
649 1.4.2.6 yamt if (lock < (uintptr_t)base + sz) {
650 1.4.2.6 yamt lockdebug_abort1(ld, lk, func,
651 1.4.2.6 yamt "allocation contains active lock", !cold);
652 1.4.2.6 yamt return;
653 1.4.2.4 yamt }
654 1.4.2.4 yamt lockdebug_unlock(lk);
655 1.4.2.4 yamt }
656 1.4.2.4 yamt
657 1.4.2.4 yamt /*
658 1.4.2.2 yamt * lockdebug_dump:
659 1.4.2.2 yamt *
660 1.4.2.2 yamt * Dump information about a lock on panic, or for DDB.
661 1.4.2.2 yamt */
662 1.4.2.2 yamt static void
663 1.4.2.2 yamt lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...))
664 1.4.2.2 yamt {
665 1.4.2.2 yamt int sleeper = (ld->ld_flags & LD_SLEEPER);
666 1.4.2.2 yamt
667 1.4.2.2 yamt (*pr)(
668 1.4.2.2 yamt "lock address : %#018lx type : %18s\n"
669 1.4.2.2 yamt "shared holds : %18u exclusive: %18u\n"
670 1.4.2.2 yamt "shares wanted: %18u exclusive: %18u\n"
671 1.4.2.2 yamt "current cpu : %18u last held: %18u\n"
672 1.4.2.2 yamt "current lwp : %#018lx last held: %#018lx\n"
673 1.4.2.4 yamt "last locked : %#018lx unlocked : %#018lx\n"
674 1.4.2.4 yamt "initialized : %#018lx\n",
675 1.4.2.2 yamt (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"),
676 1.4.2.2 yamt (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0),
677 1.4.2.2 yamt (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant,
678 1.4.2.2 yamt (unsigned)cpu_number(), (unsigned)ld->ld_cpu,
679 1.4.2.2 yamt (long)curlwp, (long)ld->ld_lwp,
680 1.4.2.4 yamt (long)ld->ld_locked, (long)ld->ld_unlocked,
681 1.4.2.4 yamt (long)ld->ld_initaddr);
682 1.4.2.2 yamt
683 1.4.2.2 yamt if (ld->ld_lockops->lo_dump != NULL)
684 1.4.2.2 yamt (*ld->ld_lockops->lo_dump)(ld->ld_lock);
685 1.4.2.2 yamt
686 1.4.2.2 yamt if (sleeper) {
687 1.4.2.2 yamt (*pr)("\n");
688 1.4.2.2 yamt turnstile_print(ld->ld_lock, pr);
689 1.4.2.2 yamt }
690 1.4.2.2 yamt }
691 1.4.2.2 yamt
692 1.4.2.2 yamt /*
693 1.4.2.2 yamt * lockdebug_dump:
694 1.4.2.2 yamt *
695 1.4.2.2 yamt * Dump information about a known lock.
696 1.4.2.2 yamt */
697 1.4.2.3 yamt static void
698 1.4.2.2 yamt lockdebug_abort1(lockdebug_t *ld, lockdebuglk_t *lk, const char *func,
699 1.4.2.4 yamt const char *msg, bool dopanic)
700 1.4.2.2 yamt {
701 1.4.2.2 yamt
702 1.4.2.2 yamt printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name,
703 1.4.2.2 yamt func, msg);
704 1.4.2.2 yamt lockdebug_dump(ld, printf_nolog);
705 1.4.2.2 yamt lockdebug_unlock(lk);
706 1.4.2.2 yamt printf_nolog("\n");
707 1.4.2.4 yamt if (dopanic)
708 1.4.2.4 yamt panic("LOCKDEBUG");
709 1.4.2.2 yamt }
710 1.4.2.2 yamt
711 1.4.2.2 yamt #endif /* LOCKDEBUG */
712 1.4.2.2 yamt
713 1.4.2.2 yamt /*
714 1.4.2.2 yamt * lockdebug_lock_print:
715 1.4.2.2 yamt *
716 1.4.2.2 yamt * Handle the DDB 'show lock' command.
717 1.4.2.2 yamt */
718 1.4.2.2 yamt #ifdef DDB
719 1.4.2.2 yamt void
720 1.4.2.2 yamt lockdebug_lock_print(void *addr, void (*pr)(const char *, ...))
721 1.4.2.2 yamt {
722 1.4.2.2 yamt #ifdef LOCKDEBUG
723 1.4.2.2 yamt lockdebug_t *ld;
724 1.4.2.2 yamt
725 1.4.2.2 yamt TAILQ_FOREACH(ld, &ld_all, ld_achain) {
726 1.4.2.2 yamt if (ld->ld_lock == addr) {
727 1.4.2.2 yamt lockdebug_dump(ld, pr);
728 1.4.2.2 yamt return;
729 1.4.2.2 yamt }
730 1.4.2.2 yamt }
731 1.4.2.2 yamt (*pr)("Sorry, no record of a lock with address %p found.\n", addr);
732 1.4.2.2 yamt #else
733 1.4.2.2 yamt (*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n");
734 1.4.2.2 yamt #endif /* LOCKDEBUG */
735 1.4.2.2 yamt }
736 1.4.2.2 yamt #endif /* DDB */
737 1.4.2.2 yamt
738 1.4.2.2 yamt /*
739 1.4.2.2 yamt * lockdebug_abort:
740 1.4.2.2 yamt *
741 1.4.2.2 yamt * An error has been trapped - dump lock info and call panic().
742 1.4.2.2 yamt */
743 1.4.2.2 yamt void
744 1.4.2.6 yamt lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func,
745 1.4.2.6 yamt const char *msg)
746 1.4.2.2 yamt {
747 1.4.2.2 yamt #ifdef LOCKDEBUG
748 1.4.2.2 yamt lockdebug_t *ld;
749 1.4.2.2 yamt lockdebuglk_t *lk;
750 1.4.2.2 yamt
751 1.4.2.6 yamt if ((ld = lockdebug_lookup(lock, &lk)) != NULL) {
752 1.4.2.4 yamt lockdebug_abort1(ld, lk, func, msg, true);
753 1.4.2.2 yamt /* NOTREACHED */
754 1.4.2.2 yamt }
755 1.4.2.2 yamt #endif /* LOCKDEBUG */
756 1.4.2.2 yamt
757 1.4.2.2 yamt printf_nolog("%s error: %s: %s\n\n"
758 1.4.2.2 yamt "lock address : %#018lx\n"
759 1.4.2.2 yamt "current cpu : %18d\n"
760 1.4.2.2 yamt "current lwp : %#018lx\n",
761 1.4.2.2 yamt ops->lo_name, func, msg, (long)lock, (int)cpu_number(),
762 1.4.2.2 yamt (long)curlwp);
763 1.4.2.2 yamt
764 1.4.2.2 yamt (*ops->lo_dump)(lock);
765 1.4.2.2 yamt
766 1.4.2.2 yamt printf_nolog("\n");
767 1.4.2.2 yamt panic("lock error");
768 1.4.2.2 yamt }
769