tools/testing/radix-tree/idr-test.c

   1 /*
   2  * idr-test.c: Test the IDR API
   3  * Copyright (c) 2016 Matthew Wilcox <willy@infradead.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  */
  14 #include <linux/bitmap.h>
  15 #include <linux/idr.h>
  16 #include <linux/slab.h>
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19
  20 #include "test.h"
  21
  22 #define DUMMY_PTR       ((void *)0x12)
  23
  24 int item_idr_free(int id, void *p, void *data)
  25 {
  26         struct item *item = p;
  27         assert(item->index == id);
  28         free(p);
  29
  30         return 0;
  31 }
  32
  33 void item_idr_remove(struct idr *idr, int id)
  34 {
  35         struct item *item = idr_find(idr, id);
  36         assert(item->index == id);
  37         idr_remove(idr, id);
  38         free(item);
  39 }
  40
  41 void idr_alloc_test(void)
  42 {
  43         unsigned long i;
  44         DEFINE_IDR(idr);
  45
  46         assert(idr_alloc_cyclic(&idr, DUMMY_PTR, 0, 0x4000, GFP_KERNEL) == 0);
  47         assert(idr_alloc_cyclic(&idr, DUMMY_PTR, 0x3ffd, 0x4000, GFP_KERNEL) == 0x3ffd);
  48         idr_remove(&idr, 0x3ffd);
  49         idr_remove(&idr, 0);
  50
  51         for (i = 0x3ffe; i < 0x4003; i++) {
  52                 int id;
  53                 struct item *item;
  54
  55                 if (i < 0x4000)
  56                         item = item_create(i, 0);
  57                 else
  58                         item = item_create(i - 0x3fff, 0);
  59
  60                 id = idr_alloc_cyclic(&idr, item, 1, 0x4000, GFP_KERNEL);
  61                 assert(id == item->index);
  62         }
  63
  64         idr_for_each(&idr, item_idr_free, &idr);
  65         idr_destroy(&idr);
  66 }
  67
  68 void idr_replace_test(void)
  69 {
  70         DEFINE_IDR(idr);
  71
  72         idr_alloc(&idr, (void *)-1, 10, 11, GFP_KERNEL);
  73         idr_replace(&idr, &idr, 10);
  74
  75         idr_destroy(&idr);
  76 }
  77
  78 /*
  79  * Unlike the radix tree, you can put a NULL pointer -- with care -- into
  80  * the IDR.  Some interfaces, like idr_find() do not distinguish between
  81  * "present, value is NULL" and "not present", but that's exactly what some
  82  * users want.
  83  */
  84 void idr_null_test(void)
  85 {
  86         int i;
  87         DEFINE_IDR(idr);
  88
  89         assert(idr_is_empty(&idr));
  90
  91         assert(idr_alloc(&idr, NULL, 0, 0, GFP_KERNEL) == 0);
  92         assert(!idr_is_empty(&idr));
  93         idr_remove(&idr, 0);
  94         assert(idr_is_empty(&idr));
  95
  96         assert(idr_alloc(&idr, NULL, 0, 0, GFP_KERNEL) == 0);
  97         assert(!idr_is_empty(&idr));
  98         idr_destroy(&idr);
  99         assert(idr_is_empty(&idr));
 100
 101         for (i = 0; i < 10; i++) {
 102                 assert(idr_alloc(&idr, NULL, 0, 0, GFP_KERNEL) == i);
 103         }
 104
 105         assert(idr_replace(&idr, DUMMY_PTR, 3) == NULL);
 106         assert(idr_replace(&idr, DUMMY_PTR, 4) == NULL);
 107         assert(idr_replace(&idr, NULL, 4) == DUMMY_PTR);
 108         assert(idr_replace(&idr, DUMMY_PTR, 11) == ERR_PTR(-ENOENT));
 109         idr_remove(&idr, 5);
 110         assert(idr_alloc(&idr, NULL, 0, 0, GFP_KERNEL) == 5);
 111         idr_remove(&idr, 5);
 112
 113         for (i = 0; i < 9; i++) {
 114                 idr_remove(&idr, i);
 115                 assert(!idr_is_empty(&idr));
 116         }
 117         idr_remove(&idr, 8);
 118         assert(!idr_is_empty(&idr));
 119         idr_remove(&idr, 9);
 120         assert(idr_is_empty(&idr));
 121
 122         assert(idr_alloc(&idr, NULL, 0, 0, GFP_KERNEL) == 0);
 123         assert(idr_replace(&idr, DUMMY_PTR, 3) == ERR_PTR(-ENOENT));
 124         assert(idr_replace(&idr, DUMMY_PTR, 0) == NULL);
 125         assert(idr_replace(&idr, NULL, 0) == DUMMY_PTR);
 126
 127         idr_destroy(&idr);
 128         assert(idr_is_empty(&idr));
 129
 130         for (i = 1; i < 10; i++) {
 131                 assert(idr_alloc(&idr, NULL, 1, 0, GFP_KERNEL) == i);
 132         }
 133
 134         idr_destroy(&idr);
 135         assert(idr_is_empty(&idr));
 136 }
 137
 138 void idr_nowait_test(void)
 139 {
 140         unsigned int i;
 141         DEFINE_IDR(idr);
 142
 143         idr_preload(GFP_KERNEL);
 144
 145         for (i = 0; i < 3; i++) {
 146                 struct item *item = item_create(i, 0);
 147                 assert(idr_alloc(&idr, item, i, i + 1, GFP_NOWAIT) == i);
 148         }
 149
 150         idr_preload_end();
 151
 152         idr_for_each(&idr, item_idr_free, &idr);
 153         idr_destroy(&idr);
 154 }
 155
 156 void idr_get_next_test(int base)
 157 {
 158         unsigned long i;
 159         int nextid;
 160         DEFINE_IDR(idr);
 161         idr_init_base(&idr, base);
 162
 163         int indices[] = {4, 7, 9, 15, 65, 128, 1000, 99999, 0};
 164
 165         for(i = 0; indices[i]; i++) {
 166                 struct item *item = item_create(indices[i], 0);
 167                 assert(idr_alloc(&idr, item, indices[i], indices[i+1],
 168                                  GFP_KERNEL) == indices[i]);
 169         }
 170
 171         for(i = 0, nextid = 0; indices[i]; i++) {
 172                 idr_get_next(&idr, &nextid);
 173                 assert(nextid == indices[i]);
 174                 nextid++;
 175         }
 176
 177         idr_for_each(&idr, item_idr_free, &idr);
 178         idr_destroy(&idr);
 179 }
 180
 181 void idr_checks(void)
 182 {
 183         unsigned long i;
 184         DEFINE_IDR(idr);
 185
 186         for (i = 0; i < 10000; i++) {
 187                 struct item *item = item_create(i, 0);
 188                 assert(idr_alloc(&idr, item, 0, 20000, GFP_KERNEL) == i);
 189         }
 190
 191         assert(idr_alloc(&idr, DUMMY_PTR, 5, 30, GFP_KERNEL) < 0);
 192
 193         for (i = 0; i < 5000; i++)
 194                 item_idr_remove(&idr, i);
 195
 196         idr_remove(&idr, 3);
 197
 198         idr_for_each(&idr, item_idr_free, &idr);
 199         idr_destroy(&idr);
 200
 201         assert(idr_is_empty(&idr));
 202
 203         idr_remove(&idr, 3);
 204         idr_remove(&idr, 0);
 205
 206         for (i = INT_MAX - 3UL; i < INT_MAX + 1UL; i++) {
 207                 struct item *item = item_create(i, 0);
 208                 assert(idr_alloc(&idr, item, i, i + 10, GFP_KERNEL) == i);
 209         }
 210         assert(idr_alloc(&idr, DUMMY_PTR, i - 2, i, GFP_KERNEL) == -ENOSPC);
 211         assert(idr_alloc(&idr, DUMMY_PTR, i - 2, i + 10, GFP_KERNEL) == -ENOSPC);
 212
 213         idr_for_each(&idr, item_idr_free, &idr);
 214         idr_destroy(&idr);
 215         idr_destroy(&idr);
 216
 217         assert(idr_is_empty(&idr));
 218
 219         idr_set_cursor(&idr, INT_MAX - 3UL);
 220         for (i = INT_MAX - 3UL; i < INT_MAX + 3UL; i++) {
 221                 struct item *item;
 222                 unsigned int id;
 223                 if (i <= INT_MAX)
 224                         item = item_create(i, 0);
 225                 else
 226                         item = item_create(i - INT_MAX - 1, 0);
 227
 228                 id = idr_alloc_cyclic(&idr, item, 0, 0, GFP_KERNEL);
 229                 assert(id == item->index);
 230         }
 231
 232         idr_for_each(&idr, item_idr_free, &idr);
 233         idr_destroy(&idr);
 234         assert(idr_is_empty(&idr));
 235
 236         for (i = 1; i < 10000; i++) {
 237                 struct item *item = item_create(i, 0);
 238                 assert(idr_alloc(&idr, item, 1, 20000, GFP_KERNEL) == i);
 239         }
 240
 241         idr_for_each(&idr, item_idr_free, &idr);
 242         idr_destroy(&idr);
 243
 244         idr_replace_test();
 245         idr_alloc_test();
 246         idr_null_test();
 247         idr_nowait_test();
 248         idr_get_next_test(0);
 249         idr_get_next_test(1);
 250         idr_get_next_test(4);
 251 }
 252
 253 /*
 254  * Check that we get the correct error when we run out of memory doing
 255  * allocations.  To ensure we run out of memory, just "forget" to preload.
 256  * The first test is for not having a bitmap available, and the second test
 257  * is for not being able to allocate a level of the radix tree.
 258  */
 259 void ida_check_nomem(void)
 260 {
 261         DEFINE_IDA(ida);
 262         int id, err;
 263
 264         err = ida_get_new_above(&ida, 256, &id);
 265         assert(err == -EAGAIN);
 266         err = ida_get_new_above(&ida, 1UL << 30, &id);
 267         assert(err == -EAGAIN);
 268 }
 269
 270 /*
 271  * Check what happens when we fill a leaf and then delete it.  This may
 272  * discover mishandling of IDR_FREE.
 273  */
 274 void ida_check_leaf(void)
 275 {
 276         DEFINE_IDA(ida);
 277         int id;
 278         unsigned long i;
 279
 280         for (i = 0; i < IDA_BITMAP_BITS; i++) {
 281                 assert(ida_pre_get(&ida, GFP_KERNEL));
 282                 assert(!ida_get_new(&ida, &id));
 283                 assert(id == i);
 284         }
 285
 286         ida_destroy(&ida);
 287         assert(ida_is_empty(&ida));
 288
 289         assert(ida_pre_get(&ida, GFP_KERNEL));
 290         assert(!ida_get_new(&ida, &id));
 291         assert(id == 0);
 292         ida_destroy(&ida);
 293         assert(ida_is_empty(&ida));
 294 }
 295
 296 /*
 297  * Check handling of conversions between exceptional entries and full bitmaps.
 298  */
 299 void ida_check_conv(void)
 300 {
 301         DEFINE_IDA(ida);
 302         int id;
 303         unsigned long i;
 304
 305         for (i = 0; i < IDA_BITMAP_BITS * 2; i += IDA_BITMAP_BITS) {
 306                 assert(ida_pre_get(&ida, GFP_KERNEL));
 307                 assert(!ida_get_new_above(&ida, i + 1, &id));
 308                 assert(id == i + 1);
 309                 assert(!ida_get_new_above(&ida, i + BITS_PER_LONG, &id));
 310                 assert(id == i + BITS_PER_LONG);
 311                 ida_remove(&ida, i + 1);
 312                 ida_remove(&ida, i + BITS_PER_LONG);
 313                 assert(ida_is_empty(&ida));
 314         }
 315
 316         assert(ida_pre_get(&ida, GFP_KERNEL));
 317
 318         for (i = 0; i < IDA_BITMAP_BITS * 2; i++) {
 319                 assert(ida_pre_get(&ida, GFP_KERNEL));
 320                 assert(!ida_get_new(&ida, &id));
 321                 assert(id == i);
 322         }
 323
 324         for (i = IDA_BITMAP_BITS * 2; i > 0; i--) {
 325                 ida_remove(&ida, i - 1);
 326         }
 327         assert(ida_is_empty(&ida));
 328
 329         for (i = 0; i < IDA_BITMAP_BITS + BITS_PER_LONG - 4; i++) {
 330                 assert(ida_pre_get(&ida, GFP_KERNEL));
 331                 assert(!ida_get_new(&ida, &id));
 332                 assert(id == i);
 333         }
 334
 335         for (i = IDA_BITMAP_BITS + BITS_PER_LONG - 4; i > 0; i--) {
 336                 ida_remove(&ida, i - 1);
 337         }
 338         assert(ida_is_empty(&ida));
 339
 340         radix_tree_cpu_dead(1);
 341         for (i = 0; i < 1000000; i++) {
 342                 int err = ida_get_new(&ida, &id);
 343                 if (err == -EAGAIN) {
 344                         assert((i % IDA_BITMAP_BITS) == (BITS_PER_LONG - 2));
 345                         assert(ida_pre_get(&ida, GFP_KERNEL));
 346                         err = ida_get_new(&ida, &id);
 347                 } else {
 348                         assert((i % IDA_BITMAP_BITS) != (BITS_PER_LONG - 2));
 349                 }
 350                 assert(!err);
 351                 assert(id == i);
 352         }
 353         ida_destroy(&ida);
 354 }
 355
 356 /*
 357  * Check allocations up to and slightly above the maximum allowed (2^31-1) ID.
 358  * Allocating up to 2^31-1 should succeed, and then allocating the next one
 359  * should fail.
 360  */
 361 void ida_check_max(void)
 362 {
 363         DEFINE_IDA(ida);
 364         int id, err;
 365         unsigned long i, j;
 366
 367         for (j = 1; j < 65537; j *= 2) {
 368                 unsigned long base = (1UL << 31) - j;
 369                 for (i = 0; i < j; i++) {
 370                         assert(ida_pre_get(&ida, GFP_KERNEL));
 371                         assert(!ida_get_new_above(&ida, base, &id));
 372                         assert(id == base + i);
 373                 }
 374                 assert(ida_pre_get(&ida, GFP_KERNEL));
 375                 err = ida_get_new_above(&ida, base, &id);
 376                 assert(err == -ENOSPC);
 377                 ida_destroy(&ida);
 378                 assert(ida_is_empty(&ida));
 379                 rcu_barrier();
 380         }
 381 }
 382
 383 void ida_check_random(void)
 384 {
 385         DEFINE_IDA(ida);
 386         DECLARE_BITMAP(bitmap, 2048);
 387         int id, err;
 388         unsigned int i;
 389         time_t s = time(NULL);
 390
 391  repeat:
 392         memset(bitmap, 0, sizeof(bitmap));
 393         for (i = 0; i < 100000; i++) {
 394                 int i = rand();
 395                 int bit = i & 2047;
 396                 if (test_bit(bit, bitmap)) {
 397                         __clear_bit(bit, bitmap);
 398                         ida_remove(&ida, bit);
 399                 } else {
 400                         __set_bit(bit, bitmap);
 401                         do {
 402                                 ida_pre_get(&ida, GFP_KERNEL);
 403                                 err = ida_get_new_above(&ida, bit, &id);
 404                         } while (err == -EAGAIN);
 405                         assert(!err);
 406                         assert(id == bit);
 407                 }
 408         }
 409         ida_destroy(&ida);
 410         if (time(NULL) < s + 10)
 411                 goto repeat;
 412 }
 413
 414 void ida_simple_get_remove_test(void)
 415 {
 416         DEFINE_IDA(ida);
 417         unsigned long i;
 418
 419         for (i = 0; i < 10000; i++) {
 420                 assert(ida_simple_get(&ida, 0, 20000, GFP_KERNEL) == i);
 421         }
 422         assert(ida_simple_get(&ida, 5, 30, GFP_KERNEL) < 0);
 423
 424         for (i = 0; i < 10000; i++) {
 425                 ida_simple_remove(&ida, i);
 426         }
 427         assert(ida_is_empty(&ida));
 428
 429         ida_destroy(&ida);
 430 }
 431
 432 void ida_checks(void)
 433 {
 434         DEFINE_IDA(ida);
 435         int id;
 436         unsigned long i;
 437
 438         radix_tree_cpu_dead(1);
 439         ida_check_nomem();
 440
 441         for (i = 0; i < 10000; i++) {
 442                 assert(ida_pre_get(&ida, GFP_KERNEL));
 443                 assert(!ida_get_new(&ida, &id));
 444                 assert(id == i);
 445         }
 446
 447         ida_remove(&ida, 20);
 448         ida_remove(&ida, 21);
 449         for (i = 0; i < 3; i++) {
 450                 assert(ida_pre_get(&ida, GFP_KERNEL));
 451                 assert(!ida_get_new(&ida, &id));
 452                 if (i == 2)
 453                         assert(id == 10000);
 454         }
 455
 456         for (i = 0; i < 5000; i++)
 457                 ida_remove(&ida, i);
 458
 459         assert(ida_pre_get(&ida, GFP_KERNEL));
 460         assert(!ida_get_new_above(&ida, 5000, &id));
 461         assert(id == 10001);
 462
 463         ida_destroy(&ida);
 464
 465         assert(ida_is_empty(&ida));
 466
 467         assert(ida_pre_get(&ida, GFP_KERNEL));
 468         assert(!ida_get_new_above(&ida, 1, &id));
 469         assert(id == 1);
 470
 471         ida_remove(&ida, id);
 472         assert(ida_is_empty(&ida));
 473         ida_destroy(&ida);
 474         assert(ida_is_empty(&ida));
 475
 476         assert(ida_pre_get(&ida, GFP_KERNEL));
 477         assert(!ida_get_new_above(&ida, 1, &id));
 478         ida_destroy(&ida);
 479         assert(ida_is_empty(&ida));
 480
 481         assert(ida_pre_get(&ida, GFP_KERNEL));
 482         assert(!ida_get_new_above(&ida, 1, &id));
 483         assert(id == 1);
 484         assert(ida_pre_get(&ida, GFP_KERNEL));
 485         assert(!ida_get_new_above(&ida, 1025, &id));
 486         assert(id == 1025);
 487         assert(ida_pre_get(&ida, GFP_KERNEL));
 488         assert(!ida_get_new_above(&ida, 10000, &id));
 489         assert(id == 10000);
 490         ida_remove(&ida, 1025);
 491         ida_destroy(&ida);
 492         assert(ida_is_empty(&ida));
 493
 494         ida_check_leaf();
 495         ida_check_max();
 496         ida_check_conv();
 497         ida_check_random();
 498         ida_simple_get_remove_test();
 499
 500         radix_tree_cpu_dead(1);
 501 }
 502
 503 static void *ida_random_fn(void *arg)
 504 {
 505         rcu_register_thread();
 506         ida_check_random();
 507         rcu_unregister_thread();
 508         return NULL;
 509 }
 510
 511 void ida_thread_tests(void)
 512 {
 513         pthread_t threads[20];
 514         int i;
 515
 516         for (i = 0; i < ARRAY_SIZE(threads); i++)
 517                 if (pthread_create(&threads[i], NULL, ida_random_fn, NULL)) {
 518                         perror("creating ida thread");
 519                         exit(1);
 520                 }
 521
 522         while (i--)
 523                 pthread_join(threads[i], NULL);
 524 }
 525
 526 int __weak main(void)
 527 {
 528         radix_tree_init();
 529         idr_checks();
 530         ida_checks();
 531         ida_thread_tests();
 532         radix_tree_cpu_dead(1);
 533         rcu_barrier();
 534         if (nr_allocated)
 535                 printf("nr_allocated = %d\n", nr_allocated);
 536         return 0;
 537 }