1 /* 2 * lib/locking-selftest.c 3 * 4 * Testsuite for various locking APIs: spinlocks, rwlocks, 5 * mutexes and rw-semaphores. 6 * 7 * It is checking both false positives and false negatives. 8 * 9 * Started by Ingo Molnar: 10 * 11 * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> 12 */ 13 #include <linux/rwsem.h> 14 #include <linux/mutex.h> 15 #include <linux/sched.h> 16 #include <linux/delay.h> 17 #include <linux/module.h> 18 #include <linux/lockdep.h> 19 #include <linux/spinlock.h> 20 #include <linux/kallsyms.h> 21 #include <linux/interrupt.h> 22 #include <linux/debug_locks.h> 23 #include <linux/irqflags.h> 24 25 /* 26 * Change this to 1 if you want to see the failure printouts: 27 */ 28 static unsigned int debug_locks_verbose; 29 30 static int __init setup_debug_locks_verbose(char *str) 31 { 32 get_option(&str, &debug_locks_verbose); 33 34 return 1; 35 } 36 37 __setup("debug_locks_verbose=", setup_debug_locks_verbose); 38 39 #define FAILURE 0 40 #define SUCCESS 1 41 42 #define LOCKTYPE_SPIN 0x1 43 #define LOCKTYPE_RWLOCK 0x2 44 #define LOCKTYPE_MUTEX 0x4 45 #define LOCKTYPE_RWSEM 0x8 46 47 /* 48 * Normal standalone locks, for the circular and irq-context 49 * dependency tests: 50 */ 51 static DEFINE_SPINLOCK(lock_A); 52 static DEFINE_SPINLOCK(lock_B); 53 static DEFINE_SPINLOCK(lock_C); 54 static DEFINE_SPINLOCK(lock_D); 55 56 static DEFINE_RWLOCK(rwlock_A); 57 static DEFINE_RWLOCK(rwlock_B); 58 static DEFINE_RWLOCK(rwlock_C); 59 static DEFINE_RWLOCK(rwlock_D); 60 61 static DEFINE_MUTEX(mutex_A); 62 static DEFINE_MUTEX(mutex_B); 63 static DEFINE_MUTEX(mutex_C); 64 static DEFINE_MUTEX(mutex_D); 65 66 static DECLARE_RWSEM(rwsem_A); 67 static DECLARE_RWSEM(rwsem_B); 68 static DECLARE_RWSEM(rwsem_C); 69 static DECLARE_RWSEM(rwsem_D); 70 71 /* 72 * Locks that we initialize dynamically as well so that 73 * e.g. X1 and X2 becomes two instances of the same class, 74 * but X* and Y* are different classes. We do this so that 75 * we do not trigger a real lockup: 76 */ 77 static DEFINE_SPINLOCK(lock_X1); 78 static DEFINE_SPINLOCK(lock_X2); 79 static DEFINE_SPINLOCK(lock_Y1); 80 static DEFINE_SPINLOCK(lock_Y2); 81 static DEFINE_SPINLOCK(lock_Z1); 82 static DEFINE_SPINLOCK(lock_Z2); 83 84 static DEFINE_RWLOCK(rwlock_X1); 85 static DEFINE_RWLOCK(rwlock_X2); 86 static DEFINE_RWLOCK(rwlock_Y1); 87 static DEFINE_RWLOCK(rwlock_Y2); 88 static DEFINE_RWLOCK(rwlock_Z1); 89 static DEFINE_RWLOCK(rwlock_Z2); 90 91 static DEFINE_MUTEX(mutex_X1); 92 static DEFINE_MUTEX(mutex_X2); 93 static DEFINE_MUTEX(mutex_Y1); 94 static DEFINE_MUTEX(mutex_Y2); 95 static DEFINE_MUTEX(mutex_Z1); 96 static DEFINE_MUTEX(mutex_Z2); 97 98 static DECLARE_RWSEM(rwsem_X1); 99 static DECLARE_RWSEM(rwsem_X2); 100 static DECLARE_RWSEM(rwsem_Y1); 101 static DECLARE_RWSEM(rwsem_Y2); 102 static DECLARE_RWSEM(rwsem_Z1); 103 static DECLARE_RWSEM(rwsem_Z2); 104 105 /* 106 * non-inlined runtime initializers, to let separate locks share 107 * the same lock-class: 108 */ 109 #define INIT_CLASS_FUNC(class) \ 110 static noinline void \ 111 init_class_##class(spinlock_t *lock, rwlock_t *rwlock, struct mutex *mutex, \ 112 struct rw_semaphore *rwsem) \ 113 { \ 114 spin_lock_init(lock); \ 115 rwlock_init(rwlock); \ 116 mutex_init(mutex); \ 117 init_rwsem(rwsem); \ 118 } 119 120 INIT_CLASS_FUNC(X) 121 INIT_CLASS_FUNC(Y) 122 INIT_CLASS_FUNC(Z) 123 124 static void init_shared_classes(void) 125 { 126 init_class_X(&lock_X1, &rwlock_X1, &mutex_X1, &rwsem_X1); 127 init_class_X(&lock_X2, &rwlock_X2, &mutex_X2, &rwsem_X2); 128 129 init_class_Y(&lock_Y1, &rwlock_Y1, &mutex_Y1, &rwsem_Y1); 130 init_class_Y(&lock_Y2, &rwlock_Y2, &mutex_Y2, &rwsem_Y2); 131 132 init_class_Z(&lock_Z1, &rwlock_Z1, &mutex_Z1, &rwsem_Z1); 133 init_class_Z(&lock_Z2, &rwlock_Z2, &mutex_Z2, &rwsem_Z2); 134 } 135 136 /* 137 * For spinlocks and rwlocks we also do hardirq-safe / softirq-safe tests. 138 * The following functions use a lock from a simulated hardirq/softirq 139 * context, causing the locks to be marked as hardirq-safe/softirq-safe: 140 */ 141 142 #define HARDIRQ_DISABLE local_irq_disable 143 #define HARDIRQ_ENABLE local_irq_enable 144 145 #define HARDIRQ_ENTER() \ 146 local_irq_disable(); \ 147 __irq_enter(); \ 148 WARN_ON(!in_irq()); 149 150 #define HARDIRQ_EXIT() \ 151 __irq_exit(); \ 152 local_irq_enable(); 153 154 #define SOFTIRQ_DISABLE local_bh_disable 155 #define SOFTIRQ_ENABLE local_bh_enable 156 157 #define SOFTIRQ_ENTER() \ 158 local_bh_disable(); \ 159 local_irq_disable(); \ 160 lockdep_softirq_enter(); \ 161 WARN_ON(!in_softirq()); 162 163 #define SOFTIRQ_EXIT() \ 164 lockdep_softirq_exit(); \ 165 local_irq_enable(); \ 166 local_bh_enable(); 167 168 /* 169 * Shortcuts for lock/unlock API variants, to keep 170 * the testcases compact: 171 */ 172 #define L(x) spin_lock(&lock_##x) 173 #define U(x) spin_unlock(&lock_##x) 174 #define LU(x) L(x); U(x) 175 #define SI(x) spin_lock_init(&lock_##x) 176 177 #define WL(x) write_lock(&rwlock_##x) 178 #define WU(x) write_unlock(&rwlock_##x) 179 #define WLU(x) WL(x); WU(x) 180 181 #define RL(x) read_lock(&rwlock_##x) 182 #define RU(x) read_unlock(&rwlock_##x) 183 #define RLU(x) RL(x); RU(x) 184 #define RWI(x) rwlock_init(&rwlock_##x) 185 186 #define ML(x) mutex_lock(&mutex_##x) 187 #define MU(x) mutex_unlock(&mutex_##x) 188 #define MI(x) mutex_init(&mutex_##x) 189 190 #define WSL(x) down_write(&rwsem_##x) 191 #define WSU(x) up_write(&rwsem_##x) 192 193 #define RSL(x) down_read(&rwsem_##x) 194 #define RSU(x) up_read(&rwsem_##x) 195 #define RWSI(x) init_rwsem(&rwsem_##x) 196 197 #define LOCK_UNLOCK_2(x,y) LOCK(x); LOCK(y); UNLOCK(y); UNLOCK(x) 198 199 /* 200 * Generate different permutations of the same testcase, using 201 * the same basic lock-dependency/state events: 202 */ 203 204 #define GENERATE_TESTCASE(name) \ 205 \ 206 static void name(void) { E(); } 207 208 #define GENERATE_PERMUTATIONS_2_EVENTS(name) \ 209 \ 210 static void name##_12(void) { E1(); E2(); } \ 211 static void name##_21(void) { E2(); E1(); } 212 213 #define GENERATE_PERMUTATIONS_3_EVENTS(name) \ 214 \ 215 static void name##_123(void) { E1(); E2(); E3(); } \ 216 static void name##_132(void) { E1(); E3(); E2(); } \ 217 static void name##_213(void) { E2(); E1(); E3(); } \ 218 static void name##_231(void) { E2(); E3(); E1(); } \ 219 static void name##_312(void) { E3(); E1(); E2(); } \ 220 static void name##_321(void) { E3(); E2(); E1(); } 221 222 /* 223 * AA deadlock: 224 */ 225 226 #define E() \ 227 \ 228 LOCK(X1); \ 229 LOCK(X2); /* this one should fail */ 230 231 /* 232 * 6 testcases: 233 */ 234 #include "locking-selftest-spin.h" 235 GENERATE_TESTCASE(AA_spin) 236 #include "locking-selftest-wlock.h" 237 GENERATE_TESTCASE(AA_wlock) 238 #include "locking-selftest-rlock.h" 239 GENERATE_TESTCASE(AA_rlock) 240 #include "locking-selftest-mutex.h" 241 GENERATE_TESTCASE(AA_mutex) 242 #include "locking-selftest-wsem.h" 243 GENERATE_TESTCASE(AA_wsem) 244 #include "locking-selftest-rsem.h" 245 GENERATE_TESTCASE(AA_rsem) 246 247 #undef E 248 249 /* 250 * Special-case for read-locking, they are 251 * allowed to recurse on the same lock class: 252 */ 253 static void rlock_AA1(void) 254 { 255 RL(X1); 256 RL(X1); // this one should NOT fail 257 } 258 259 static void rlock_AA1B(void) 260 { 261 RL(X1); 262 RL(X2); // this one should NOT fail 263 } 264 265 static void rsem_AA1(void) 266 { 267 RSL(X1); 268 RSL(X1); // this one should fail 269 } 270 271 static void rsem_AA1B(void) 272 { 273 RSL(X1); 274 RSL(X2); // this one should fail 275 } 276 /* 277 * The mixing of read and write locks is not allowed: 278 */ 279 static void rlock_AA2(void) 280 { 281 RL(X1); 282 WL(X2); // this one should fail 283 } 284 285 static void rsem_AA2(void) 286 { 287 RSL(X1); 288 WSL(X2); // this one should fail 289 } 290 291 static void rlock_AA3(void) 292 { 293 WL(X1); 294 RL(X2); // this one should fail 295 } 296 297 static void rsem_AA3(void) 298 { 299 WSL(X1); 300 RSL(X2); // this one should fail 301 } 302 303 /* 304 * ABBA deadlock: 305 */ 306 307 #define E() \ 308 \ 309 LOCK_UNLOCK_2(A, B); \ 310 LOCK_UNLOCK_2(B, A); /* fail */ 311 312 /* 313 * 6 testcases: 314 */ 315 #include "locking-selftest-spin.h" 316 GENERATE_TESTCASE(ABBA_spin) 317 #include "locking-selftest-wlock.h" 318 GENERATE_TESTCASE(ABBA_wlock) 319 #include "locking-selftest-rlock.h" 320 GENERATE_TESTCASE(ABBA_rlock) 321 #include "locking-selftest-mutex.h" 322 GENERATE_TESTCASE(ABBA_mutex) 323 #include "locking-selftest-wsem.h" 324 GENERATE_TESTCASE(ABBA_wsem) 325 #include "locking-selftest-rsem.h" 326 GENERATE_TESTCASE(ABBA_rsem) 327 328 #undef E 329 330 /* 331 * AB BC CA deadlock: 332 */ 333 334 #define E() \ 335 \ 336 LOCK_UNLOCK_2(A, B); \ 337 LOCK_UNLOCK_2(B, C); \ 338 LOCK_UNLOCK_2(C, A); /* fail */ 339 340 /* 341 * 6 testcases: 342 */ 343 #include "locking-selftest-spin.h" 344 GENERATE_TESTCASE(ABBCCA_spin) 345 #include "locking-selftest-wlock.h" 346 GENERATE_TESTCASE(ABBCCA_wlock) 347 #include "locking-selftest-rlock.h" 348 GENERATE_TESTCASE(ABBCCA_rlock) 349 #include "locking-selftest-mutex.h" 350 GENERATE_TESTCASE(ABBCCA_mutex) 351 #include "locking-selftest-wsem.h" 352 GENERATE_TESTCASE(ABBCCA_wsem) 353 #include "locking-selftest-rsem.h" 354 GENERATE_TESTCASE(ABBCCA_rsem) 355 356 #undef E 357 358 /* 359 * AB CA BC deadlock: 360 */ 361 362 #define E() \ 363 \ 364 LOCK_UNLOCK_2(A, B); \ 365 LOCK_UNLOCK_2(C, A); \ 366 LOCK_UNLOCK_2(B, C); /* fail */ 367 368 /* 369 * 6 testcases: 370 */ 371 #include "locking-selftest-spin.h" 372 GENERATE_TESTCASE(ABCABC_spin) 373 #include "locking-selftest-wlock.h" 374 GENERATE_TESTCASE(ABCABC_wlock) 375 #include "locking-selftest-rlock.h" 376 GENERATE_TESTCASE(ABCABC_rlock) 377 #include "locking-selftest-mutex.h" 378 GENERATE_TESTCASE(ABCABC_mutex) 379 #include "locking-selftest-wsem.h" 380 GENERATE_TESTCASE(ABCABC_wsem) 381 #include "locking-selftest-rsem.h" 382 GENERATE_TESTCASE(ABCABC_rsem) 383 384 #undef E 385 386 /* 387 * AB BC CD DA deadlock: 388 */ 389 390 #define E() \ 391 \ 392 LOCK_UNLOCK_2(A, B); \ 393 LOCK_UNLOCK_2(B, C); \ 394 LOCK_UNLOCK_2(C, D); \ 395 LOCK_UNLOCK_2(D, A); /* fail */ 396 397 /* 398 * 6 testcases: 399 */ 400 #include "locking-selftest-spin.h" 401 GENERATE_TESTCASE(ABBCCDDA_spin) 402 #include "locking-selftest-wlock.h" 403 GENERATE_TESTCASE(ABBCCDDA_wlock) 404 #include "locking-selftest-rlock.h" 405 GENERATE_TESTCASE(ABBCCDDA_rlock) 406 #include "locking-selftest-mutex.h" 407 GENERATE_TESTCASE(ABBCCDDA_mutex) 408 #include "locking-selftest-wsem.h" 409 GENERATE_TESTCASE(ABBCCDDA_wsem) 410 #include "locking-selftest-rsem.h" 411 GENERATE_TESTCASE(ABBCCDDA_rsem) 412 413 #undef E 414 415 /* 416 * AB CD BD DA deadlock: 417 */ 418 #define E() \ 419 \ 420 LOCK_UNLOCK_2(A, B); \ 421 LOCK_UNLOCK_2(C, D); \ 422 LOCK_UNLOCK_2(B, D); \ 423 LOCK_UNLOCK_2(D, A); /* fail */ 424 425 /* 426 * 6 testcases: 427 */ 428 #include "locking-selftest-spin.h" 429 GENERATE_TESTCASE(ABCDBDDA_spin) 430 #include "locking-selftest-wlock.h" 431 GENERATE_TESTCASE(ABCDBDDA_wlock) 432 #include "locking-selftest-rlock.h" 433 GENERATE_TESTCASE(ABCDBDDA_rlock) 434 #include "locking-selftest-mutex.h" 435 GENERATE_TESTCASE(ABCDBDDA_mutex) 436 #include "locking-selftest-wsem.h" 437 GENERATE_TESTCASE(ABCDBDDA_wsem) 438 #include "locking-selftest-rsem.h" 439 GENERATE_TESTCASE(ABCDBDDA_rsem) 440 441 #undef E 442 443 /* 444 * AB CD BC DA deadlock: 445 */ 446 #define E() \ 447 \ 448 LOCK_UNLOCK_2(A, B); \ 449 LOCK_UNLOCK_2(C, D); \ 450 LOCK_UNLOCK_2(B, C); \ 451 LOCK_UNLOCK_2(D, A); /* fail */ 452 453 /* 454 * 6 testcases: 455 */ 456 #include "locking-selftest-spin.h" 457 GENERATE_TESTCASE(ABCDBCDA_spin) 458 #include "locking-selftest-wlock.h" 459 GENERATE_TESTCASE(ABCDBCDA_wlock) 460 #include "locking-selftest-rlock.h" 461 GENERATE_TESTCASE(ABCDBCDA_rlock) 462 #include "locking-selftest-mutex.h" 463 GENERATE_TESTCASE(ABCDBCDA_mutex) 464 #include "locking-selftest-wsem.h" 465 GENERATE_TESTCASE(ABCDBCDA_wsem) 466 #include "locking-selftest-rsem.h" 467 GENERATE_TESTCASE(ABCDBCDA_rsem) 468 469 #undef E 470 471 /* 472 * Double unlock: 473 */ 474 #define E() \ 475 \ 476 LOCK(A); \ 477 UNLOCK(A); \ 478 UNLOCK(A); /* fail */ 479 480 /* 481 * 6 testcases: 482 */ 483 #include "locking-selftest-spin.h" 484 GENERATE_TESTCASE(double_unlock_spin) 485 #include "locking-selftest-wlock.h" 486 GENERATE_TESTCASE(double_unlock_wlock) 487 #include "locking-selftest-rlock.h" 488 GENERATE_TESTCASE(double_unlock_rlock) 489 #include "locking-selftest-mutex.h" 490 GENERATE_TESTCASE(double_unlock_mutex) 491 #include "locking-selftest-wsem.h" 492 GENERATE_TESTCASE(double_unlock_wsem) 493 #include "locking-selftest-rsem.h" 494 GENERATE_TESTCASE(double_unlock_rsem) 495 496 #undef E 497 498 /* 499 * Bad unlock ordering: 500 */ 501 #define E() \ 502 \ 503 LOCK(A); \ 504 LOCK(B); \ 505 UNLOCK(A); /* fail */ \ 506 UNLOCK(B); 507 508 /* 509 * 6 testcases: 510 */ 511 #include "locking-selftest-spin.h" 512 GENERATE_TESTCASE(bad_unlock_order_spin) 513 #include "locking-selftest-wlock.h" 514 GENERATE_TESTCASE(bad_unlock_order_wlock) 515 #include "locking-selftest-rlock.h" 516 GENERATE_TESTCASE(bad_unlock_order_rlock) 517 #include "locking-selftest-mutex.h" 518 GENERATE_TESTCASE(bad_unlock_order_mutex) 519 #include "locking-selftest-wsem.h" 520 GENERATE_TESTCASE(bad_unlock_order_wsem) 521 #include "locking-selftest-rsem.h" 522 GENERATE_TESTCASE(bad_unlock_order_rsem) 523 524 #undef E 525 526 /* 527 * initializing a held lock: 528 */ 529 #define E() \ 530 \ 531 LOCK(A); \ 532 INIT(A); /* fail */ 533 534 /* 535 * 6 testcases: 536 */ 537 #include "locking-selftest-spin.h" 538 GENERATE_TESTCASE(init_held_spin) 539 #include "locking-selftest-wlock.h" 540 GENERATE_TESTCASE(init_held_wlock) 541 #include "locking-selftest-rlock.h" 542 GENERATE_TESTCASE(init_held_rlock) 543 #include "locking-selftest-mutex.h" 544 GENERATE_TESTCASE(init_held_mutex) 545 #include "locking-selftest-wsem.h" 546 GENERATE_TESTCASE(init_held_wsem) 547 #include "locking-selftest-rsem.h" 548 GENERATE_TESTCASE(init_held_rsem) 549 550 #undef E 551 552 /* 553 * locking an irq-safe lock with irqs enabled: 554 */ 555 #define E1() \ 556 \ 557 IRQ_ENTER(); \ 558 LOCK(A); \ 559 UNLOCK(A); \ 560 IRQ_EXIT(); 561 562 #define E2() \ 563 \ 564 LOCK(A); \ 565 UNLOCK(A); 566 567 /* 568 * Generate 24 testcases: 569 */ 570 #include "locking-selftest-spin-hardirq.h" 571 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin) 572 573 #include "locking-selftest-rlock-hardirq.h" 574 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock) 575 576 #include "locking-selftest-wlock-hardirq.h" 577 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_wlock) 578 579 #include "locking-selftest-spin-softirq.h" 580 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_spin) 581 582 #include "locking-selftest-rlock-softirq.h" 583 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock) 584 585 #include "locking-selftest-wlock-softirq.h" 586 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock) 587 588 #undef E1 589 #undef E2 590 591 /* 592 * Enabling hardirqs with a softirq-safe lock held: 593 */ 594 #define E1() \ 595 \ 596 SOFTIRQ_ENTER(); \ 597 LOCK(A); \ 598 UNLOCK(A); \ 599 SOFTIRQ_EXIT(); 600 601 #define E2() \ 602 \ 603 HARDIRQ_DISABLE(); \ 604 LOCK(A); \ 605 HARDIRQ_ENABLE(); \ 606 UNLOCK(A); 607 608 /* 609 * Generate 12 testcases: 610 */ 611 #include "locking-selftest-spin.h" 612 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_spin) 613 614 #include "locking-selftest-wlock.h" 615 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_wlock) 616 617 #include "locking-selftest-rlock.h" 618 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock) 619 620 #undef E1 621 #undef E2 622 623 /* 624 * Enabling irqs with an irq-safe lock held: 625 */ 626 #define E1() \ 627 \ 628 IRQ_ENTER(); \ 629 LOCK(A); \ 630 UNLOCK(A); \ 631 IRQ_EXIT(); 632 633 #define E2() \ 634 \ 635 IRQ_DISABLE(); \ 636 LOCK(A); \ 637 IRQ_ENABLE(); \ 638 UNLOCK(A); 639 640 /* 641 * Generate 24 testcases: 642 */ 643 #include "locking-selftest-spin-hardirq.h" 644 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin) 645 646 #include "locking-selftest-rlock-hardirq.h" 647 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock) 648 649 #include "locking-selftest-wlock-hardirq.h" 650 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_wlock) 651 652 #include "locking-selftest-spin-softirq.h" 653 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_spin) 654 655 #include "locking-selftest-rlock-softirq.h" 656 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock) 657 658 #include "locking-selftest-wlock-softirq.h" 659 GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock) 660 661 #undef E1 662 #undef E2 663 664 /* 665 * Acquiring a irq-unsafe lock while holding an irq-safe-lock: 666 */ 667 #define E1() \ 668 \ 669 LOCK(A); \ 670 LOCK(B); \ 671 UNLOCK(B); \ 672 UNLOCK(A); \ 673 674 #define E2() \ 675 \ 676 LOCK(B); \ 677 UNLOCK(B); 678 679 #define E3() \ 680 \ 681 IRQ_ENTER(); \ 682 LOCK(A); \ 683 UNLOCK(A); \ 684 IRQ_EXIT(); 685 686 /* 687 * Generate 36 testcases: 688 */ 689 #include "locking-selftest-spin-hardirq.h" 690 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin) 691 692 #include "locking-selftest-rlock-hardirq.h" 693 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock) 694 695 #include "locking-selftest-wlock-hardirq.h" 696 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_wlock) 697 698 #include "locking-selftest-spin-softirq.h" 699 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_spin) 700 701 #include "locking-selftest-rlock-softirq.h" 702 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock) 703 704 #include "locking-selftest-wlock-softirq.h" 705 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock) 706 707 #undef E1 708 #undef E2 709 #undef E3 710 711 /* 712 * If a lock turns into softirq-safe, but earlier it took 713 * a softirq-unsafe lock: 714 */ 715 716 #define E1() \ 717 IRQ_DISABLE(); \ 718 LOCK(A); \ 719 LOCK(B); \ 720 UNLOCK(B); \ 721 UNLOCK(A); \ 722 IRQ_ENABLE(); 723 724 #define E2() \ 725 LOCK(B); \ 726 UNLOCK(B); 727 728 #define E3() \ 729 IRQ_ENTER(); \ 730 LOCK(A); \ 731 UNLOCK(A); \ 732 IRQ_EXIT(); 733 734 /* 735 * Generate 36 testcases: 736 */ 737 #include "locking-selftest-spin-hardirq.h" 738 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin) 739 740 #include "locking-selftest-rlock-hardirq.h" 741 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock) 742 743 #include "locking-selftest-wlock-hardirq.h" 744 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_wlock) 745 746 #include "locking-selftest-spin-softirq.h" 747 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_spin) 748 749 #include "locking-selftest-rlock-softirq.h" 750 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock) 751 752 #include "locking-selftest-wlock-softirq.h" 753 GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock) 754 755 #undef E1 756 #undef E2 757 #undef E3 758 759 /* 760 * read-lock / write-lock irq inversion. 761 * 762 * Deadlock scenario: 763 * 764 * CPU#1 is at #1, i.e. it has write-locked A, but has not 765 * taken B yet. 766 * 767 * CPU#2 is at #2, i.e. it has locked B. 768 * 769 * Hardirq hits CPU#2 at point #2 and is trying to read-lock A. 770 * 771 * The deadlock occurs because CPU#1 will spin on B, and CPU#2 772 * will spin on A. 773 */ 774 775 #define E1() \ 776 \ 777 IRQ_DISABLE(); \ 778 WL(A); \ 779 LOCK(B); \ 780 UNLOCK(B); \ 781 WU(A); \ 782 IRQ_ENABLE(); 783 784 #define E2() \ 785 \ 786 LOCK(B); \ 787 UNLOCK(B); 788 789 #define E3() \ 790 \ 791 IRQ_ENTER(); \ 792 RL(A); \ 793 RU(A); \ 794 IRQ_EXIT(); 795 796 /* 797 * Generate 36 testcases: 798 */ 799 #include "locking-selftest-spin-hardirq.h" 800 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_spin) 801 802 #include "locking-selftest-rlock-hardirq.h" 803 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_rlock) 804 805 #include "locking-selftest-wlock-hardirq.h" 806 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_wlock) 807 808 #include "locking-selftest-spin-softirq.h" 809 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_spin) 810 811 #include "locking-selftest-rlock-softirq.h" 812 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_rlock) 813 814 #include "locking-selftest-wlock-softirq.h" 815 GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock) 816 817 #undef E1 818 #undef E2 819 #undef E3 820 821 /* 822 * read-lock / write-lock recursion that is actually safe. 823 */ 824 825 #define E1() \ 826 \ 827 IRQ_DISABLE(); \ 828 WL(A); \ 829 WU(A); \ 830 IRQ_ENABLE(); 831 832 #define E2() \ 833 \ 834 RL(A); \ 835 RU(A); \ 836 837 #define E3() \ 838 \ 839 IRQ_ENTER(); \ 840 RL(A); \ 841 L(B); \ 842 U(B); \ 843 RU(A); \ 844 IRQ_EXIT(); 845 846 /* 847 * Generate 12 testcases: 848 */ 849 #include "locking-selftest-hardirq.h" 850 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_hard) 851 852 #include "locking-selftest-softirq.h" 853 GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft) 854 855 #undef E1 856 #undef E2 857 #undef E3 858 859 /* 860 * read-lock / write-lock recursion that is unsafe. 861 */ 862 863 #define E1() \ 864 \ 865 IRQ_DISABLE(); \ 866 L(B); \ 867 WL(A); \ 868 WU(A); \ 869 U(B); \ 870 IRQ_ENABLE(); 871 872 #define E2() \ 873 \ 874 RL(A); \ 875 RU(A); \ 876 877 #define E3() \ 878 \ 879 IRQ_ENTER(); \ 880 L(B); \ 881 U(B); \ 882 IRQ_EXIT(); 883 884 /* 885 * Generate 12 testcases: 886 */ 887 #include "locking-selftest-hardirq.h" 888 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_hard) 889 890 #include "locking-selftest-softirq.h" 891 // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_soft) 892 893 #ifdef CONFIG_DEBUG_LOCK_ALLOC 894 # define I_SPINLOCK(x) lockdep_reset_lock(&lock_##x.dep_map) 895 # define I_RWLOCK(x) lockdep_reset_lock(&rwlock_##x.dep_map) 896 # define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map) 897 # define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map) 898 #else 899 # define I_SPINLOCK(x) 900 # define I_RWLOCK(x) 901 # define I_MUTEX(x) 902 # define I_RWSEM(x) 903 #endif 904 905 #define I1(x) \ 906 do { \ 907 I_SPINLOCK(x); \ 908 I_RWLOCK(x); \ 909 I_MUTEX(x); \ 910 I_RWSEM(x); \ 911 } while (0) 912 913 #define I2(x) \ 914 do { \ 915 spin_lock_init(&lock_##x); \ 916 rwlock_init(&rwlock_##x); \ 917 mutex_init(&mutex_##x); \ 918 init_rwsem(&rwsem_##x); \ 919 } while (0) 920 921 static void reset_locks(void) 922 { 923 local_irq_disable(); 924 I1(A); I1(B); I1(C); I1(D); 925 I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2); 926 lockdep_reset(); 927 I2(A); I2(B); I2(C); I2(D); 928 init_shared_classes(); 929 local_irq_enable(); 930 } 931 932 #undef I 933 934 static int testcase_total; 935 static int testcase_successes; 936 static int expected_testcase_failures; 937 static int unexpected_testcase_failures; 938 939 static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask) 940 { 941 unsigned long saved_preempt_count = preempt_count(); 942 int expected_failure = 0; 943 944 WARN_ON(irqs_disabled()); 945 946 testcase_fn(); 947 /* 948 * Filter out expected failures: 949 */ 950 #ifndef CONFIG_PROVE_LOCKING 951 if ((lockclass_mask & LOCKTYPE_SPIN) && debug_locks != expected) 952 expected_failure = 1; 953 if ((lockclass_mask & LOCKTYPE_RWLOCK) && debug_locks != expected) 954 expected_failure = 1; 955 if ((lockclass_mask & LOCKTYPE_MUTEX) && debug_locks != expected) 956 expected_failure = 1; 957 if ((lockclass_mask & LOCKTYPE_RWSEM) && debug_locks != expected) 958 expected_failure = 1; 959 #endif 960 if (debug_locks != expected) { 961 if (expected_failure) { 962 expected_testcase_failures++; 963 printk("failed|"); 964 } else { 965 unexpected_testcase_failures++; 966 967 printk("FAILED|"); 968 dump_stack(); 969 } 970 } else { 971 testcase_successes++; 972 printk(" ok |"); 973 } 974 testcase_total++; 975 976 if (debug_locks_verbose) 977 printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n", 978 lockclass_mask, debug_locks, expected); 979 /* 980 * Some tests (e.g. double-unlock) might corrupt the preemption 981 * count, so restore it: 982 */ 983 preempt_count() = saved_preempt_count; 984 #ifdef CONFIG_TRACE_IRQFLAGS 985 if (softirq_count()) 986 current->softirqs_enabled = 0; 987 else 988 current->softirqs_enabled = 1; 989 #endif 990 991 reset_locks(); 992 } 993 994 static inline void print_testname(const char *testname) 995 { 996 printk("%33s:", testname); 997 } 998 999 #define DO_TESTCASE_1(desc, name, nr) \ 1000 print_testname(desc"/"#nr); \ 1001 dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK); \ 1002 printk("\n"); 1003 1004 #define DO_TESTCASE_1B(desc, name, nr) \ 1005 print_testname(desc"/"#nr); \ 1006 dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK); \ 1007 printk("\n"); 1008 1009 #define DO_TESTCASE_3(desc, name, nr) \ 1010 print_testname(desc"/"#nr); \ 1011 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN); \ 1012 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \ 1013 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \ 1014 printk("\n"); 1015 1016 #define DO_TESTCASE_3RW(desc, name, nr) \ 1017 print_testname(desc"/"#nr); \ 1018 dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\ 1019 dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \ 1020 dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \ 1021 printk("\n"); 1022 1023 #define DO_TESTCASE_6(desc, name) \ 1024 print_testname(desc); \ 1025 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \ 1026 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \ 1027 dotest(name##_rlock, FAILURE, LOCKTYPE_RWLOCK); \ 1028 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \ 1029 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \ 1030 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \ 1031 printk("\n"); 1032 1033 #define DO_TESTCASE_6_SUCCESS(desc, name) \ 1034 print_testname(desc); \ 1035 dotest(name##_spin, SUCCESS, LOCKTYPE_SPIN); \ 1036 dotest(name##_wlock, SUCCESS, LOCKTYPE_RWLOCK); \ 1037 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \ 1038 dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX); \ 1039 dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM); \ 1040 dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM); \ 1041 printk("\n"); 1042 1043 /* 1044 * 'read' variant: rlocks must not trigger. 1045 */ 1046 #define DO_TESTCASE_6R(desc, name) \ 1047 print_testname(desc); \ 1048 dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \ 1049 dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \ 1050 dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \ 1051 dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \ 1052 dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \ 1053 dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \ 1054 printk("\n"); 1055 1056 #define DO_TESTCASE_2I(desc, name, nr) \ 1057 DO_TESTCASE_1("hard-"desc, name##_hard, nr); \ 1058 DO_TESTCASE_1("soft-"desc, name##_soft, nr); 1059 1060 #define DO_TESTCASE_2IB(desc, name, nr) \ 1061 DO_TESTCASE_1B("hard-"desc, name##_hard, nr); \ 1062 DO_TESTCASE_1B("soft-"desc, name##_soft, nr); 1063 1064 #define DO_TESTCASE_6I(desc, name, nr) \ 1065 DO_TESTCASE_3("hard-"desc, name##_hard, nr); \ 1066 DO_TESTCASE_3("soft-"desc, name##_soft, nr); 1067 1068 #define DO_TESTCASE_6IRW(desc, name, nr) \ 1069 DO_TESTCASE_3RW("hard-"desc, name##_hard, nr); \ 1070 DO_TESTCASE_3RW("soft-"desc, name##_soft, nr); 1071 1072 #define DO_TESTCASE_2x3(desc, name) \ 1073 DO_TESTCASE_3(desc, name, 12); \ 1074 DO_TESTCASE_3(desc, name, 21); 1075 1076 #define DO_TESTCASE_2x6(desc, name) \ 1077 DO_TESTCASE_6I(desc, name, 12); \ 1078 DO_TESTCASE_6I(desc, name, 21); 1079 1080 #define DO_TESTCASE_6x2(desc, name) \ 1081 DO_TESTCASE_2I(desc, name, 123); \ 1082 DO_TESTCASE_2I(desc, name, 132); \ 1083 DO_TESTCASE_2I(desc, name, 213); \ 1084 DO_TESTCASE_2I(desc, name, 231); \ 1085 DO_TESTCASE_2I(desc, name, 312); \ 1086 DO_TESTCASE_2I(desc, name, 321); 1087 1088 #define DO_TESTCASE_6x2B(desc, name) \ 1089 DO_TESTCASE_2IB(desc, name, 123); \ 1090 DO_TESTCASE_2IB(desc, name, 132); \ 1091 DO_TESTCASE_2IB(desc, name, 213); \ 1092 DO_TESTCASE_2IB(desc, name, 231); \ 1093 DO_TESTCASE_2IB(desc, name, 312); \ 1094 DO_TESTCASE_2IB(desc, name, 321); 1095 1096 #define DO_TESTCASE_6x6(desc, name) \ 1097 DO_TESTCASE_6I(desc, name, 123); \ 1098 DO_TESTCASE_6I(desc, name, 132); \ 1099 DO_TESTCASE_6I(desc, name, 213); \ 1100 DO_TESTCASE_6I(desc, name, 231); \ 1101 DO_TESTCASE_6I(desc, name, 312); \ 1102 DO_TESTCASE_6I(desc, name, 321); 1103 1104 #define DO_TESTCASE_6x6RW(desc, name) \ 1105 DO_TESTCASE_6IRW(desc, name, 123); \ 1106 DO_TESTCASE_6IRW(desc, name, 132); \ 1107 DO_TESTCASE_6IRW(desc, name, 213); \ 1108 DO_TESTCASE_6IRW(desc, name, 231); \ 1109 DO_TESTCASE_6IRW(desc, name, 312); \ 1110 DO_TESTCASE_6IRW(desc, name, 321); 1111 1112 1113 void locking_selftest(void) 1114 { 1115 /* 1116 * Got a locking failure before the selftest ran? 1117 */ 1118 if (!debug_locks) { 1119 printk("----------------------------------\n"); 1120 printk("| Locking API testsuite disabled |\n"); 1121 printk("----------------------------------\n"); 1122 return; 1123 } 1124 1125 /* 1126 * Run the testsuite: 1127 */ 1128 printk("------------------------\n"); 1129 printk("| Locking API testsuite:\n"); 1130 printk("----------------------------------------------------------------------------\n"); 1131 printk(" | spin |wlock |rlock |mutex | wsem | rsem |\n"); 1132 printk(" --------------------------------------------------------------------------\n"); 1133 1134 init_shared_classes(); 1135 debug_locks_silent = !debug_locks_verbose; 1136 1137 DO_TESTCASE_6R("A-A deadlock", AA); 1138 DO_TESTCASE_6R("A-B-B-A deadlock", ABBA); 1139 DO_TESTCASE_6R("A-B-B-C-C-A deadlock", ABBCCA); 1140 DO_TESTCASE_6R("A-B-C-A-B-C deadlock", ABCABC); 1141 DO_TESTCASE_6R("A-B-B-C-C-D-D-A deadlock", ABBCCDDA); 1142 DO_TESTCASE_6R("A-B-C-D-B-D-D-A deadlock", ABCDBDDA); 1143 DO_TESTCASE_6R("A-B-C-D-B-C-D-A deadlock", ABCDBCDA); 1144 DO_TESTCASE_6("double unlock", double_unlock); 1145 DO_TESTCASE_6("initialize held", init_held); 1146 DO_TESTCASE_6_SUCCESS("bad unlock order", bad_unlock_order); 1147 1148 printk(" --------------------------------------------------------------------------\n"); 1149 print_testname("recursive read-lock"); 1150 printk(" |"); 1151 dotest(rlock_AA1, SUCCESS, LOCKTYPE_RWLOCK); 1152 printk(" |"); 1153 dotest(rsem_AA1, FAILURE, LOCKTYPE_RWSEM); 1154 printk("\n"); 1155 1156 print_testname("recursive read-lock #2"); 1157 printk(" |"); 1158 dotest(rlock_AA1B, SUCCESS, LOCKTYPE_RWLOCK); 1159 printk(" |"); 1160 dotest(rsem_AA1B, FAILURE, LOCKTYPE_RWSEM); 1161 printk("\n"); 1162 1163 print_testname("mixed read-write-lock"); 1164 printk(" |"); 1165 dotest(rlock_AA2, FAILURE, LOCKTYPE_RWLOCK); 1166 printk(" |"); 1167 dotest(rsem_AA2, FAILURE, LOCKTYPE_RWSEM); 1168 printk("\n"); 1169 1170 print_testname("mixed write-read-lock"); 1171 printk(" |"); 1172 dotest(rlock_AA3, FAILURE, LOCKTYPE_RWLOCK); 1173 printk(" |"); 1174 dotest(rsem_AA3, FAILURE, LOCKTYPE_RWSEM); 1175 printk("\n"); 1176 1177 printk(" --------------------------------------------------------------------------\n"); 1178 1179 /* 1180 * irq-context testcases: 1181 */ 1182 DO_TESTCASE_2x6("irqs-on + irq-safe-A", irqsafe1); 1183 DO_TESTCASE_2x3("sirq-safe-A => hirqs-on", irqsafe2A); 1184 DO_TESTCASE_2x6("safe-A + irqs-on", irqsafe2B); 1185 DO_TESTCASE_6x6("safe-A + unsafe-B #1", irqsafe3); 1186 DO_TESTCASE_6x6("safe-A + unsafe-B #2", irqsafe4); 1187 DO_TESTCASE_6x6RW("irq lock-inversion", irq_inversion); 1188 1189 DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion); 1190 // DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2); 1191 1192 if (unexpected_testcase_failures) { 1193 printk("-----------------------------------------------------------------\n"); 1194 debug_locks = 0; 1195 printk("BUG: %3d unexpected failures (out of %3d) - debugging disabled! |\n", 1196 unexpected_testcase_failures, testcase_total); 1197 printk("-----------------------------------------------------------------\n"); 1198 } else if (expected_testcase_failures && testcase_successes) { 1199 printk("--------------------------------------------------------\n"); 1200 printk("%3d out of %3d testcases failed, as expected. |\n", 1201 expected_testcase_failures, testcase_total); 1202 printk("----------------------------------------------------\n"); 1203 debug_locks = 1; 1204 } else if (expected_testcase_failures && !testcase_successes) { 1205 printk("--------------------------------------------------------\n"); 1206 printk("All %3d testcases failed, as expected. |\n", 1207 expected_testcase_failures); 1208 printk("----------------------------------------\n"); 1209 debug_locks = 1; 1210 } else { 1211 printk("-------------------------------------------------------\n"); 1212 printk("Good, all %3d testcases passed! |\n", 1213 testcase_successes); 1214 printk("---------------------------------\n"); 1215 debug_locks = 1; 1216 } 1217 debug_locks_silent = 0; 1218 } 1219