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