1 /* $NetBSD: subr_lockdebug.c,v 1.43 2010/09/25 01:42:39 matt Exp $ */ 2 3 /*- 4 * Copyright (c) 2006, 2007, 2008 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Basic lock debugging code shared among lock primitives. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.43 2010/09/25 01:42:39 matt Exp $"); 38 39 #include "opt_ddb.h" 40 41 #include <sys/param.h> 42 #include <sys/proc.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/kmem.h> 46 #include <sys/lockdebug.h> 47 #include <sys/sleepq.h> 48 #include <sys/cpu.h> 49 #include <sys/atomic.h> 50 #include <sys/lock.h> 51 #include <sys/rbtree.h> 52 53 #include <machine/lock.h> 54 55 unsigned int ld_panic; 56 57 #ifdef LOCKDEBUG 58 59 #define LD_BATCH_SHIFT 9 60 #define LD_BATCH (1 << LD_BATCH_SHIFT) 61 #define LD_BATCH_MASK (LD_BATCH - 1) 62 #define LD_MAX_LOCKS 1048576 63 #define LD_SLOP 16 64 65 #define LD_LOCKED 0x01 66 #define LD_SLEEPER 0x02 67 68 #define LD_WRITE_LOCK 0x80000000 69 70 typedef struct lockdebug { 71 struct rb_node ld_rb_node; 72 __cpu_simple_lock_t ld_spinlock; 73 _TAILQ_ENTRY(struct lockdebug, volatile) ld_chain; 74 _TAILQ_ENTRY(struct lockdebug, volatile) ld_achain; 75 volatile void *ld_lock; 76 lockops_t *ld_lockops; 77 struct lwp *ld_lwp; 78 uintptr_t ld_locked; 79 uintptr_t ld_unlocked; 80 uintptr_t ld_initaddr; 81 uint16_t ld_shares; 82 uint16_t ld_cpu; 83 uint8_t ld_flags; 84 uint8_t ld_shwant; /* advisory */ 85 uint8_t ld_exwant; /* advisory */ 86 uint8_t ld_unused; 87 } volatile lockdebug_t; 88 89 typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t; 90 91 __cpu_simple_lock_t ld_mod_lk; 92 lockdebuglist_t ld_free = TAILQ_HEAD_INITIALIZER(ld_free); 93 lockdebuglist_t ld_all = TAILQ_HEAD_INITIALIZER(ld_all); 94 int ld_nfree; 95 int ld_freeptr; 96 int ld_recurse; 97 bool ld_nomore; 98 lockdebug_t ld_prime[LD_BATCH]; 99 100 static void lockdebug_abort1(lockdebug_t *, int, const char *, 101 const char *, bool); 102 static int lockdebug_more(int); 103 static void lockdebug_init(void); 104 105 static signed int 106 ld_rbto_compare_nodes(void *ctx, const void *n1, const void *n2) 107 { 108 const lockdebug_t *ld1 = n1; 109 const lockdebug_t *ld2 = n2; 110 const uintptr_t a = (uintptr_t)ld1->ld_lock; 111 const uintptr_t b = (uintptr_t)ld2->ld_lock; 112 113 if (a < b) 114 return -1; 115 if (a > b) 116 return 1; 117 return 0; 118 } 119 120 static signed int 121 ld_rbto_compare_key(void *ctx, const void *n, const void *key) 122 { 123 const lockdebug_t *ld = n; 124 const uintptr_t a = (uintptr_t)ld->ld_lock; 125 const uintptr_t b = (uintptr_t)key; 126 127 if (a < b) 128 return -1; 129 if (a > b) 130 return 1; 131 return 0; 132 } 133 134 static rb_tree_t ld_rb_tree; 135 136 static const rb_tree_ops_t ld_rb_tree_ops = { 137 .rbto_compare_nodes = ld_rbto_compare_nodes, 138 .rbto_compare_key = ld_rbto_compare_key, 139 .rbto_node_offset = offsetof(lockdebug_t, ld_rb_node), 140 .rbto_context = NULL 141 }; 142 143 static inline lockdebug_t * 144 lockdebug_lookup1(volatile void *lock) 145 { 146 lockdebug_t *ld; 147 struct cpu_info *ci; 148 149 ci = curcpu(); 150 __cpu_simple_lock(&ci->ci_data.cpu_ld_lock); 151 ld = (lockdebug_t *)rb_tree_find_node(&ld_rb_tree, __UNVOLATILE(lock)); 152 __cpu_simple_unlock(&ci->ci_data.cpu_ld_lock); 153 if (ld == NULL) { 154 return NULL; 155 } 156 __cpu_simple_lock(&ld->ld_spinlock); 157 158 return ld; 159 } 160 161 static void 162 lockdebug_lock_cpus(void) 163 { 164 CPU_INFO_ITERATOR cii; 165 struct cpu_info *ci; 166 167 for (CPU_INFO_FOREACH(cii, ci)) { 168 __cpu_simple_lock(&ci->ci_data.cpu_ld_lock); 169 } 170 } 171 172 static void 173 lockdebug_unlock_cpus(void) 174 { 175 CPU_INFO_ITERATOR cii; 176 struct cpu_info *ci; 177 178 for (CPU_INFO_FOREACH(cii, ci)) { 179 __cpu_simple_unlock(&ci->ci_data.cpu_ld_lock); 180 } 181 } 182 183 /* 184 * lockdebug_lookup: 185 * 186 * Find a lockdebug structure by a pointer to a lock and return it locked. 187 */ 188 static inline lockdebug_t * 189 lockdebug_lookup(volatile void *lock, uintptr_t where) 190 { 191 lockdebug_t *ld; 192 193 ld = lockdebug_lookup1(lock); 194 if (ld == NULL) { 195 panic("lockdebug_lookup: uninitialized lock " 196 "(lock=%p, from=%08"PRIxPTR")", lock, where); 197 } 198 return ld; 199 } 200 201 /* 202 * lockdebug_init: 203 * 204 * Initialize the lockdebug system. Allocate an initial pool of 205 * lockdebug structures before the VM system is up and running. 206 */ 207 static void 208 lockdebug_init(void) 209 { 210 lockdebug_t *ld; 211 int i; 212 213 TAILQ_INIT(&curcpu()->ci_data.cpu_ld_locks); 214 TAILQ_INIT(&curlwp->l_ld_locks); 215 __cpu_simple_lock_init(&curcpu()->ci_data.cpu_ld_lock); 216 __cpu_simple_lock_init(&ld_mod_lk); 217 218 rb_tree_init(&ld_rb_tree, &ld_rb_tree_ops); 219 220 ld = ld_prime; 221 for (i = 1, ld++; i < LD_BATCH; i++, ld++) { 222 __cpu_simple_lock_init(&ld->ld_spinlock); 223 TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain); 224 TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain); 225 } 226 ld_freeptr = 1; 227 ld_nfree = LD_BATCH - 1; 228 } 229 230 /* 231 * lockdebug_alloc: 232 * 233 * A lock is being initialized, so allocate an associated debug 234 * structure. 235 */ 236 bool 237 lockdebug_alloc(volatile void *lock, lockops_t *lo, uintptr_t initaddr) 238 { 239 struct cpu_info *ci; 240 lockdebug_t *ld; 241 int s; 242 243 if (lo == NULL || panicstr != NULL || ld_panic) 244 return false; 245 if (ld_freeptr == 0) 246 lockdebug_init(); 247 248 s = splhigh(); 249 __cpu_simple_lock(&ld_mod_lk); 250 if ((ld = lockdebug_lookup1(lock)) != NULL) { 251 __cpu_simple_unlock(&ld_mod_lk); 252 lockdebug_abort1(ld, s, __func__, "already initialized", true); 253 return false; 254 } 255 256 /* 257 * Pinch a new debug structure. We may recurse because we call 258 * kmem_alloc(), which may need to initialize new locks somewhere 259 * down the path. If not recursing, we try to maintain at least 260 * LD_SLOP structures free, which should hopefully be enough to 261 * satisfy kmem_alloc(). If we can't provide a structure, not to 262 * worry: we'll just mark the lock as not having an ID. 263 */ 264 ci = curcpu(); 265 ci->ci_lkdebug_recurse++; 266 if (TAILQ_EMPTY(&ld_free)) { 267 if (ci->ci_lkdebug_recurse > 1 || ld_nomore) { 268 ci->ci_lkdebug_recurse--; 269 __cpu_simple_unlock(&ld_mod_lk); 270 splx(s); 271 return false; 272 } 273 s = lockdebug_more(s); 274 } else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP) { 275 s = lockdebug_more(s); 276 } 277 if ((ld = TAILQ_FIRST(&ld_free)) == NULL) { 278 __cpu_simple_unlock(&ld_mod_lk); 279 splx(s); 280 return false; 281 } 282 TAILQ_REMOVE(&ld_free, ld, ld_chain); 283 ld_nfree--; 284 ci->ci_lkdebug_recurse--; 285 286 if (ld->ld_lock != NULL) { 287 panic("lockdebug_alloc: corrupt table"); 288 } 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 ld->ld_flags = (lo->lo_type == LOCKOPS_SLEEP ? LD_SLEEPER : 0); 298 lockdebug_lock_cpus(); 299 (void)rb_tree_insert_node(&ld_rb_tree, __UNVOLATILE(ld)); 300 lockdebug_unlock_cpus(); 301 __cpu_simple_unlock(&ld_mod_lk); 302 303 splx(s); 304 return true; 305 } 306 307 /* 308 * lockdebug_free: 309 * 310 * A lock is being destroyed, so release debugging resources. 311 */ 312 void 313 lockdebug_free(volatile void *lock) 314 { 315 lockdebug_t *ld; 316 int s; 317 318 if (panicstr != NULL || ld_panic) 319 return; 320 321 s = splhigh(); 322 __cpu_simple_lock(&ld_mod_lk); 323 ld = lockdebug_lookup(lock, (uintptr_t) __builtin_return_address(0)); 324 if (ld == NULL) { 325 __cpu_simple_unlock(&ld_mod_lk); 326 panic("lockdebug_free: destroying uninitialized object %p" 327 "(ld_lock=%p)", lock, ld->ld_lock); 328 lockdebug_abort1(ld, s, __func__, "record follows", true); 329 return; 330 } 331 if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0) { 332 __cpu_simple_unlock(&ld_mod_lk); 333 lockdebug_abort1(ld, s, __func__, "is locked or in use", true); 334 return; 335 } 336 lockdebug_lock_cpus(); 337 rb_tree_remove_node(&ld_rb_tree, __UNVOLATILE(ld)); 338 lockdebug_unlock_cpus(); 339 ld->ld_lock = NULL; 340 TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain); 341 ld_nfree++; 342 __cpu_simple_unlock(&ld->ld_spinlock); 343 __cpu_simple_unlock(&ld_mod_lk); 344 splx(s); 345 } 346 347 /* 348 * lockdebug_more: 349 * 350 * Allocate a batch of debug structures and add to the free list. 351 * Must be called with ld_mod_lk held. 352 */ 353 static int 354 lockdebug_more(int s) 355 { 356 lockdebug_t *ld; 357 void *block; 358 int i, base, m; 359 360 /* 361 * Can't call kmem_alloc() if in interrupt context. XXX We could 362 * deadlock, because we don't know which locks the caller holds. 363 */ 364 if (cpu_intr_p() || (curlwp->l_pflag & LP_INTR) != 0) { 365 return s; 366 } 367 368 while (ld_nfree < LD_SLOP) { 369 __cpu_simple_unlock(&ld_mod_lk); 370 splx(s); 371 block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP); 372 s = splhigh(); 373 __cpu_simple_lock(&ld_mod_lk); 374 375 if (block == NULL) 376 return s; 377 378 if (ld_nfree > LD_SLOP) { 379 /* Somebody beat us to it. */ 380 __cpu_simple_unlock(&ld_mod_lk); 381 splx(s); 382 kmem_free(block, LD_BATCH * sizeof(lockdebug_t)); 383 s = splhigh(); 384 __cpu_simple_lock(&ld_mod_lk); 385 continue; 386 } 387 388 base = ld_freeptr; 389 ld_nfree += LD_BATCH; 390 ld = block; 391 base <<= LD_BATCH_SHIFT; 392 m = min(LD_MAX_LOCKS, base + LD_BATCH); 393 394 if (m == LD_MAX_LOCKS) 395 ld_nomore = true; 396 397 for (i = base; i < m; i++, ld++) { 398 __cpu_simple_lock_init(&ld->ld_spinlock); 399 TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain); 400 TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain); 401 } 402 403 membar_producer(); 404 } 405 406 return s; 407 } 408 409 /* 410 * lockdebug_wantlock: 411 * 412 * Process the preamble to a lock acquire. 413 */ 414 void 415 lockdebug_wantlock(volatile void *lock, uintptr_t where, bool shared, 416 bool trylock) 417 { 418 struct lwp *l = curlwp; 419 lockdebug_t *ld; 420 bool recurse; 421 int s; 422 423 (void)shared; 424 recurse = false; 425 426 if (panicstr != NULL || ld_panic) 427 return; 428 429 s = splhigh(); 430 if ((ld = lockdebug_lookup(lock, where)) == NULL) { 431 splx(s); 432 return; 433 } 434 if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0) { 435 if ((ld->ld_flags & LD_SLEEPER) != 0) { 436 if (ld->ld_lwp == l && !(shared && trylock)) 437 recurse = true; 438 } else if (ld->ld_cpu == (uint16_t)cpu_index(curcpu())) 439 recurse = true; 440 } 441 if (cpu_intr_p()) { 442 if ((ld->ld_flags & LD_SLEEPER) != 0) { 443 lockdebug_abort1(ld, s, __func__, 444 "acquiring sleep lock from interrupt context", 445 true); 446 return; 447 } 448 } 449 if (shared) 450 ld->ld_shwant++; 451 else 452 ld->ld_exwant++; 453 if (recurse) { 454 lockdebug_abort1(ld, s, __func__, "locking against myself", 455 true); 456 return; 457 } 458 __cpu_simple_unlock(&ld->ld_spinlock); 459 splx(s); 460 } 461 462 /* 463 * lockdebug_locked: 464 * 465 * Process a lock acquire operation. 466 */ 467 void 468 lockdebug_locked(volatile void *lock, void *cvlock, uintptr_t where, 469 int shared) 470 { 471 struct lwp *l = curlwp; 472 lockdebug_t *ld; 473 int s; 474 475 if (panicstr != NULL || ld_panic) 476 return; 477 478 s = splhigh(); 479 if ((ld = lockdebug_lookup(lock, where)) == NULL) { 480 splx(s); 481 return; 482 } 483 if (cvlock) { 484 KASSERT(ld->ld_lockops->lo_type == LOCKOPS_CV); 485 if (lock == (void *)&lbolt) { 486 /* nothing */ 487 } else if (ld->ld_shares++ == 0) { 488 ld->ld_locked = (uintptr_t)cvlock; 489 } else if (cvlock != (void *)ld->ld_locked) { 490 lockdebug_abort1(ld, s, __func__, "multiple locks used" 491 " with condition variable", true); 492 return; 493 } 494 } else if (shared) { 495 l->l_shlocks++; 496 ld->ld_shares++; 497 ld->ld_shwant--; 498 } else { 499 if ((ld->ld_flags & LD_LOCKED) != 0) { 500 lockdebug_abort1(ld, s, __func__, "already locked", 501 true); 502 return; 503 } 504 ld->ld_flags |= LD_LOCKED; 505 ld->ld_locked = where; 506 ld->ld_exwant--; 507 if ((ld->ld_flags & LD_SLEEPER) != 0) { 508 TAILQ_INSERT_TAIL(&l->l_ld_locks, ld, ld_chain); 509 } else { 510 TAILQ_INSERT_TAIL(&curcpu()->ci_data.cpu_ld_locks, 511 ld, ld_chain); 512 } 513 } 514 ld->ld_cpu = (uint16_t)cpu_index(curcpu()); 515 ld->ld_lwp = l; 516 __cpu_simple_unlock(&ld->ld_spinlock); 517 splx(s); 518 } 519 520 /* 521 * lockdebug_unlocked: 522 * 523 * Process a lock release operation. 524 */ 525 void 526 lockdebug_unlocked(volatile void *lock, uintptr_t where, int shared) 527 { 528 struct lwp *l = curlwp; 529 lockdebug_t *ld; 530 int s; 531 532 if (panicstr != NULL || ld_panic) 533 return; 534 535 s = splhigh(); 536 if ((ld = lockdebug_lookup(lock, where)) == NULL) { 537 splx(s); 538 return; 539 } 540 if (ld->ld_lockops->lo_type == LOCKOPS_CV) { 541 if (lock == (void *)&lbolt) { 542 /* nothing */ 543 } else { 544 ld->ld_shares--; 545 } 546 } else if (shared) { 547 if (l->l_shlocks == 0) { 548 lockdebug_abort1(ld, s, __func__, 549 "no shared locks held by LWP", true); 550 return; 551 } 552 if (ld->ld_shares == 0) { 553 lockdebug_abort1(ld, s, __func__, 554 "no shared holds on this lock", true); 555 return; 556 } 557 l->l_shlocks--; 558 ld->ld_shares--; 559 if (ld->ld_lwp == l) 560 ld->ld_lwp = NULL; 561 if (ld->ld_cpu == (uint16_t)cpu_index(curcpu())) 562 ld->ld_cpu = (uint16_t)-1; 563 } else { 564 if ((ld->ld_flags & LD_LOCKED) == 0) { 565 lockdebug_abort1(ld, s, __func__, "not locked", true); 566 return; 567 } 568 569 if ((ld->ld_flags & LD_SLEEPER) != 0) { 570 if (ld->ld_lwp != curlwp) { 571 lockdebug_abort1(ld, s, __func__, 572 "not held by current LWP", true); 573 return; 574 } 575 ld->ld_flags &= ~LD_LOCKED; 576 ld->ld_unlocked = where; 577 ld->ld_lwp = NULL; 578 TAILQ_REMOVE(&l->l_ld_locks, ld, ld_chain); 579 } else { 580 if (ld->ld_cpu != (uint16_t)cpu_index(curcpu())) { 581 lockdebug_abort1(ld, s, __func__, 582 "not held by current CPU", true); 583 return; 584 } 585 ld->ld_flags &= ~LD_LOCKED; 586 ld->ld_unlocked = where; 587 ld->ld_lwp = NULL; 588 TAILQ_REMOVE(&curcpu()->ci_data.cpu_ld_locks, ld, 589 ld_chain); 590 } 591 } 592 __cpu_simple_unlock(&ld->ld_spinlock); 593 splx(s); 594 } 595 596 /* 597 * lockdebug_wakeup: 598 * 599 * Process a wakeup on a condition variable. 600 */ 601 void 602 lockdebug_wakeup(volatile void *lock, uintptr_t where) 603 { 604 lockdebug_t *ld; 605 int s; 606 607 if (panicstr != NULL || ld_panic || lock == (void *)&lbolt) 608 return; 609 610 s = splhigh(); 611 /* Find the CV... */ 612 if ((ld = lockdebug_lookup(lock, where)) == NULL) { 613 splx(s); 614 return; 615 } 616 /* 617 * If it has any waiters, ensure that they are using the 618 * same interlock. 619 */ 620 if (ld->ld_shares != 0 && !mutex_owned((kmutex_t *)ld->ld_locked)) { 621 lockdebug_abort1(ld, s, __func__, "interlocking mutex not " 622 "held during wakeup", true); 623 return; 624 } 625 __cpu_simple_unlock(&ld->ld_spinlock); 626 splx(s); 627 } 628 629 /* 630 * lockdebug_barrier: 631 * 632 * Panic if we hold more than one specified spin lock, and optionally, 633 * if we hold sleep locks. 634 */ 635 void 636 lockdebug_barrier(volatile void *spinlock, int slplocks) 637 { 638 struct lwp *l = curlwp; 639 lockdebug_t *ld; 640 int s; 641 642 if (panicstr != NULL || ld_panic) 643 return; 644 645 s = splhigh(); 646 if ((l->l_pflag & LP_INTR) == 0) { 647 TAILQ_FOREACH(ld, &curcpu()->ci_data.cpu_ld_locks, ld_chain) { 648 if (ld->ld_lock == spinlock) { 649 continue; 650 } 651 __cpu_simple_lock(&ld->ld_spinlock); 652 lockdebug_abort1(ld, s, __func__, 653 "spin lock held", true); 654 return; 655 } 656 } 657 if (slplocks) { 658 splx(s); 659 return; 660 } 661 if ((ld = TAILQ_FIRST(&l->l_ld_locks)) != NULL) { 662 __cpu_simple_lock(&ld->ld_spinlock); 663 lockdebug_abort1(ld, s, __func__, "sleep lock held", true); 664 return; 665 } 666 splx(s); 667 if (l->l_shlocks != 0) { 668 panic("lockdebug_barrier: holding %d shared locks", 669 l->l_shlocks); 670 } 671 } 672 673 /* 674 * lockdebug_mem_check: 675 * 676 * Check for in-use locks within a memory region that is 677 * being freed. 678 */ 679 void 680 lockdebug_mem_check(const char *func, void *base, size_t sz) 681 { 682 lockdebug_t *ld; 683 struct cpu_info *ci; 684 int s; 685 686 if (panicstr != NULL || ld_panic) 687 return; 688 689 s = splhigh(); 690 ci = curcpu(); 691 __cpu_simple_lock(&ci->ci_data.cpu_ld_lock); 692 ld = (lockdebug_t *)rb_tree_find_node_geq(&ld_rb_tree, base); 693 if (ld != NULL) { 694 const uintptr_t lock = (uintptr_t)ld->ld_lock; 695 696 if ((uintptr_t)base > lock) 697 panic("%s: corrupt tree ld=%p, base=%p, sz=%zu", 698 __func__, ld, base, sz); 699 if (lock >= (uintptr_t)base + sz) 700 ld = NULL; 701 } 702 __cpu_simple_unlock(&ci->ci_data.cpu_ld_lock); 703 if (ld != NULL) { 704 __cpu_simple_lock(&ld->ld_spinlock); 705 lockdebug_abort1(ld, s, func, 706 "allocation contains active lock", !cold); 707 return; 708 } 709 splx(s); 710 } 711 712 /* 713 * lockdebug_dump: 714 * 715 * Dump information about a lock on panic, or for DDB. 716 */ 717 static void 718 lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...)) 719 { 720 int sleeper = (ld->ld_flags & LD_SLEEPER); 721 722 (*pr)( 723 "lock address : %#018lx type : %18s\n" 724 "initialized : %#018lx", 725 (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"), 726 (long)ld->ld_initaddr); 727 728 if (ld->ld_lockops->lo_type == LOCKOPS_CV) { 729 (*pr)(" interlock: %#018lx\n", ld->ld_locked); 730 } else { 731 (*pr)("\n" 732 "shared holds : %18u exclusive: %18u\n" 733 "shares wanted: %18u exclusive: %18u\n" 734 "current cpu : %18u last held: %18u\n" 735 "current lwp : %#018lx last held: %#018lx\n" 736 "last locked : %#018lx unlocked : %#018lx\n", 737 (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0), 738 (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant, 739 (unsigned)cpu_index(curcpu()), (unsigned)ld->ld_cpu, 740 (long)curlwp, (long)ld->ld_lwp, 741 (long)ld->ld_locked, (long)ld->ld_unlocked); 742 } 743 744 if (ld->ld_lockops->lo_dump != NULL) 745 (*ld->ld_lockops->lo_dump)(ld->ld_lock); 746 747 if (sleeper) { 748 (*pr)("\n"); 749 turnstile_print(ld->ld_lock, pr); 750 } 751 } 752 753 /* 754 * lockdebug_abort1: 755 * 756 * An error has been trapped - dump lock info and panic. 757 */ 758 static void 759 lockdebug_abort1(lockdebug_t *ld, int s, const char *func, 760 const char *msg, bool dopanic) 761 { 762 763 /* 764 * Don't make the situation wose if the system is already going 765 * down in flames. Once a panic is triggered, lockdebug state 766 * becomes stale and cannot be trusted. 767 */ 768 if (atomic_inc_uint_nv(&ld_panic) != 1) { 769 __cpu_simple_unlock(&ld->ld_spinlock); 770 splx(s); 771 return; 772 } 773 774 printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name, 775 func, msg); 776 lockdebug_dump(ld, printf_nolog); 777 __cpu_simple_unlock(&ld->ld_spinlock); 778 splx(s); 779 printf_nolog("\n"); 780 if (dopanic) 781 panic("LOCKDEBUG"); 782 } 783 784 #endif /* LOCKDEBUG */ 785 786 /* 787 * lockdebug_lock_print: 788 * 789 * Handle the DDB 'show lock' command. 790 */ 791 #ifdef DDB 792 void 793 lockdebug_lock_print(void *addr, void (*pr)(const char *, ...)) 794 { 795 #ifdef LOCKDEBUG 796 lockdebug_t *ld; 797 798 TAILQ_FOREACH(ld, &ld_all, ld_achain) { 799 if (ld->ld_lock == NULL) 800 continue; 801 if (addr == NULL || ld->ld_lock == addr) { 802 lockdebug_dump(ld, pr); 803 if (addr != NULL) 804 return; 805 } 806 } 807 if (addr != NULL) { 808 (*pr)("Sorry, no record of a lock with address %p found.\n", 809 addr); 810 } 811 #else 812 (*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n"); 813 #endif /* LOCKDEBUG */ 814 } 815 #endif /* DDB */ 816 817 /* 818 * lockdebug_abort: 819 * 820 * An error has been trapped - dump lock info and call panic(). 821 */ 822 void 823 lockdebug_abort(volatile void *lock, lockops_t *ops, const char *func, 824 const char *msg) 825 { 826 #ifdef LOCKDEBUG 827 lockdebug_t *ld; 828 int s; 829 830 s = splhigh(); 831 if ((ld = lockdebug_lookup(lock, 832 (uintptr_t) __builtin_return_address(0))) != NULL) { 833 lockdebug_abort1(ld, s, func, msg, true); 834 return; 835 } 836 splx(s); 837 #endif /* LOCKDEBUG */ 838 839 /* 840 * Complain first on the occurrance only. Otherwise proceeed to 841 * panic where we will `rendezvous' with other CPUs if the machine 842 * is going down in flames. 843 */ 844 if (atomic_inc_uint_nv(&ld_panic) == 1) { 845 printf_nolog("%s error: %s: %s\n\n" 846 "lock address : %#018lx\n" 847 "current cpu : %18d\n" 848 "current lwp : %#018lx\n", 849 ops->lo_name, func, msg, (long)lock, 850 (int)cpu_index(curcpu()), (long)curlwp); 851 (*ops->lo_dump)(lock); 852 printf_nolog("\n"); 853 } 854 855 panic("lock error"); 856 } 857