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(void)
 157 {
 158         unsigned long i;
 159         int nextid;
 160         DEFINE_IDR(idr);
 161
 162         int indices[] = {4, 7, 9, 15, 65, 128, 1000, 99999, 0};
 163
 164         for(i = 0; indices[i]; i++) {
 165                 struct item *item = item_create(indices[i], 0);
 166                 assert(idr_alloc(&idr, item, indices[i], indices[i+1],
 167                                  GFP_KERNEL) == indices[i]);
 168         }
 169
 170         for(i = 0, nextid = 0; indices[i]; i++) {
 171                 idr_get_next(&idr, &nextid);
 172                 assert(nextid == indices[i]);
 173                 nextid++;
 174         }
 175
 176         idr_for_each(&idr, item_idr_free, &idr);
 177         idr_destroy(&idr);
 178 }
 179
 180 void idr_checks(void)
 181 {
 182         unsigned long i;
 183         DEFINE_IDR(idr);
 184
 185         for (i = 0; i < 10000; i++) {
 186                 struct item *item = item_create(i, 0);
 187                 assert(idr_alloc(&idr, item, 0, 20000, GFP_KERNEL) == i);
 188         }
 189
 190         assert(idr_alloc(&idr, DUMMY_PTR, 5, 30, GFP_KERNEL) < 0);
 191
 192         for (i = 0; i < 5000; i++)
 193                 item_idr_remove(&idr, i);
 194
 195         idr_remove(&idr, 3);
 196
 197         idr_for_each(&idr, item_idr_free, &idr);
 198         idr_destroy(&idr);
 199
 200         assert(idr_is_empty(&idr));
 201
 202         idr_remove(&idr, 3);
 203         idr_remove(&idr, 0);
 204
 205         for (i = INT_MAX - 3UL; i < INT_MAX + 1UL; i++) {
 206                 struct item *item = item_create(i, 0);
 207                 assert(idr_alloc(&idr, item, i, i + 10, GFP_KERNEL) == i);
 208         }
 209         assert(idr_alloc(&idr, DUMMY_PTR, i - 2, i, GFP_KERNEL) == -ENOSPC);
 210
 211         idr_for_each(&idr, item_idr_free, &idr);
 212         idr_destroy(&idr);
 213         idr_destroy(&idr);
 214
 215         assert(idr_is_empty(&idr));
 216
 217         for (i = 1; i < 10000; i++) {
 218                 struct item *item = item_create(i, 0);
 219                 assert(idr_alloc(&idr, item, 1, 20000, GFP_KERNEL) == i);
 220         }
 221
 222         idr_for_each(&idr, item_idr_free, &idr);
 223         idr_destroy(&idr);
 224
 225         idr_replace_test();
 226         idr_alloc_test();
 227         idr_null_test();
 228         idr_nowait_test();
 229         idr_get_next_test();
 230 }
 231
 232 /*
 233  * Check that we get the correct error when we run out of memory doing
 234  * allocations.  To ensure we run out of memory, just "forget" to preload.
 235  * The first test is for not having a bitmap available, and the second test
 236  * is for not being able to allocate a level of the radix tree.
 237  */
 238 void ida_check_nomem(void)
 239 {
 240         DEFINE_IDA(ida);
 241         int id, err;
 242
 243         err = ida_get_new_above(&ida, 256, &id);
 244         assert(err == -EAGAIN);
 245         err = ida_get_new_above(&ida, 1UL << 30, &id);
 246         assert(err == -EAGAIN);
 247 }
 248
 249 /*
 250  * Check what happens when we fill a leaf and then delete it.  This may
 251  * discover mishandling of IDR_FREE.
 252  */
 253 void ida_check_leaf(void)
 254 {
 255         DEFINE_IDA(ida);
 256         int id;
 257         unsigned long i;
 258
 259         for (i = 0; i < IDA_BITMAP_BITS; i++) {
 260                 assert(ida_pre_get(&ida, GFP_KERNEL));
 261                 assert(!ida_get_new(&ida, &id));
 262                 assert(id == i);
 263         }
 264
 265         ida_destroy(&ida);
 266         assert(ida_is_empty(&ida));
 267
 268         assert(ida_pre_get(&ida, GFP_KERNEL));
 269         assert(!ida_get_new(&ida, &id));
 270         assert(id == 0);
 271         ida_destroy(&ida);
 272         assert(ida_is_empty(&ida));
 273 }
 274
 275 /*
 276  * Check handling of conversions between exceptional entries and full bitmaps.
 277  */
 278 void ida_check_conv(void)
 279 {
 280         DEFINE_IDA(ida);
 281         int id;
 282         unsigned long i;
 283
 284         for (i = 0; i < IDA_BITMAP_BITS * 2; i += IDA_BITMAP_BITS) {
 285                 assert(ida_pre_get(&ida, GFP_KERNEL));
 286                 assert(!ida_get_new_above(&ida, i + 1, &id));
 287                 assert(id == i + 1);
 288                 assert(!ida_get_new_above(&ida, i + BITS_PER_LONG, &id));
 289                 assert(id == i + BITS_PER_LONG);
 290                 ida_remove(&ida, i + 1);
 291                 ida_remove(&ida, i + BITS_PER_LONG);
 292                 assert(ida_is_empty(&ida));
 293         }
 294
 295         assert(ida_pre_get(&ida, GFP_KERNEL));
 296
 297         for (i = 0; i < IDA_BITMAP_BITS * 2; i++) {
 298                 assert(ida_pre_get(&ida, GFP_KERNEL));
 299                 assert(!ida_get_new(&ida, &id));
 300                 assert(id == i);
 301         }
 302
 303         for (i = IDA_BITMAP_BITS * 2; i > 0; i--) {
 304                 ida_remove(&ida, i - 1);
 305         }
 306         assert(ida_is_empty(&ida));
 307
 308         for (i = 0; i < IDA_BITMAP_BITS + BITS_PER_LONG - 4; i++) {
 309                 assert(ida_pre_get(&ida, GFP_KERNEL));
 310                 assert(!ida_get_new(&ida, &id));
 311                 assert(id == i);
 312         }
 313
 314         for (i = IDA_BITMAP_BITS + BITS_PER_LONG - 4; i > 0; i--) {
 315                 ida_remove(&ida, i - 1);
 316         }
 317         assert(ida_is_empty(&ida));
 318
 319         radix_tree_cpu_dead(1);
 320         for (i = 0; i < 1000000; i++) {
 321                 int err = ida_get_new(&ida, &id);
 322                 if (err == -EAGAIN) {
 323                         assert((i % IDA_BITMAP_BITS) == (BITS_PER_LONG - 2));
 324                         assert(ida_pre_get(&ida, GFP_KERNEL));
 325                         err = ida_get_new(&ida, &id);
 326                 } else {
 327                         assert((i % IDA_BITMAP_BITS) != (BITS_PER_LONG - 2));
 328                 }
 329                 assert(!err);
 330                 assert(id == i);
 331         }
 332         ida_destroy(&ida);
 333 }
 334
 335 /*
 336  * Check allocations up to and slightly above the maximum allowed (2^31-1) ID.
 337  * Allocating up to 2^31-1 should succeed, and then allocating the next one
 338  * should fail.
 339  */
 340 void ida_check_max(void)
 341 {
 342         DEFINE_IDA(ida);
 343         int id, err;
 344         unsigned long i, j;
 345
 346         for (j = 1; j < 65537; j *= 2) {
 347                 unsigned long base = (1UL << 31) - j;
 348                 for (i = 0; i < j; i++) {
 349                         assert(ida_pre_get(&ida, GFP_KERNEL));
 350                         assert(!ida_get_new_above(&ida, base, &id));
 351                         assert(id == base + i);
 352                 }
 353                 assert(ida_pre_get(&ida, GFP_KERNEL));
 354                 err = ida_get_new_above(&ida, base, &id);
 355                 assert(err == -ENOSPC);
 356                 ida_destroy(&ida);
 357                 assert(ida_is_empty(&ida));
 358                 rcu_barrier();
 359         }
 360 }
 361
 362 void ida_check_random(void)
 363 {
 364         DEFINE_IDA(ida);
 365         DECLARE_BITMAP(bitmap, 2048);
 366         int id, err;
 367         unsigned int i;
 368         time_t s = time(NULL);
 369
 370  repeat:
 371         memset(bitmap, 0, sizeof(bitmap));
 372         for (i = 0; i < 100000; i++) {
 373                 int i = rand();
 374                 int bit = i & 2047;
 375                 if (test_bit(bit, bitmap)) {
 376                         __clear_bit(bit, bitmap);
 377                         ida_remove(&ida, bit);
 378                 } else {
 379                         __set_bit(bit, bitmap);
 380                         do {
 381                                 ida_pre_get(&ida, GFP_KERNEL);
 382                                 err = ida_get_new_above(&ida, bit, &id);
 383                         } while (err == -ENOMEM);
 384                         assert(!err);
 385                         assert(id == bit);
 386                 }
 387         }
 388         ida_destroy(&ida);
 389         if (time(NULL) < s + 10)
 390                 goto repeat;
 391 }
 392
 393 void ida_simple_get_remove_test(void)
 394 {
 395         DEFINE_IDA(ida);
 396         unsigned long i;
 397
 398         for (i = 0; i < 10000; i++) {
 399                 assert(ida_simple_get(&ida, 0, 20000, GFP_KERNEL) == i);
 400         }
 401         assert(ida_simple_get(&ida, 5, 30, GFP_KERNEL) < 0);
 402
 403         for (i = 0; i < 10000; i++) {
 404                 ida_simple_remove(&ida, i);
 405         }
 406         assert(ida_is_empty(&ida));
 407
 408         ida_destroy(&ida);
 409 }
 410
 411 void ida_checks(void)
 412 {
 413         DEFINE_IDA(ida);
 414         int id;
 415         unsigned long i;
 416
 417         radix_tree_cpu_dead(1);
 418         ida_check_nomem();
 419
 420         for (i = 0; i < 10000; i++) {
 421                 assert(ida_pre_get(&ida, GFP_KERNEL));
 422                 assert(!ida_get_new(&ida, &id));
 423                 assert(id == i);
 424         }
 425
 426         ida_remove(&ida, 20);
 427         ida_remove(&ida, 21);
 428         for (i = 0; i < 3; i++) {
 429                 assert(ida_pre_get(&ida, GFP_KERNEL));
 430                 assert(!ida_get_new(&ida, &id));
 431                 if (i == 2)
 432                         assert(id == 10000);
 433         }
 434
 435         for (i = 0; i < 5000; i++)
 436                 ida_remove(&ida, i);
 437
 438         assert(ida_pre_get(&ida, GFP_KERNEL));
 439         assert(!ida_get_new_above(&ida, 5000, &id));
 440         assert(id == 10001);
 441
 442         ida_destroy(&ida);
 443
 444         assert(ida_is_empty(&ida));
 445
 446         assert(ida_pre_get(&ida, GFP_KERNEL));
 447         assert(!ida_get_new_above(&ida, 1, &id));
 448         assert(id == 1);
 449
 450         ida_remove(&ida, id);
 451         assert(ida_is_empty(&ida));
 452         ida_destroy(&ida);
 453         assert(ida_is_empty(&ida));
 454
 455         assert(ida_pre_get(&ida, GFP_KERNEL));
 456         assert(!ida_get_new_above(&ida, 1, &id));
 457         ida_destroy(&ida);
 458         assert(ida_is_empty(&ida));
 459
 460         assert(ida_pre_get(&ida, GFP_KERNEL));
 461         assert(!ida_get_new_above(&ida, 1, &id));
 462         assert(id == 1);
 463         assert(ida_pre_get(&ida, GFP_KERNEL));
 464         assert(!ida_get_new_above(&ida, 1025, &id));
 465         assert(id == 1025);
 466         assert(ida_pre_get(&ida, GFP_KERNEL));
 467         assert(!ida_get_new_above(&ida, 10000, &id));
 468         assert(id == 10000);
 469         ida_remove(&ida, 1025);
 470         ida_destroy(&ida);
 471         assert(ida_is_empty(&ida));
 472
 473         ida_check_leaf();
 474         ida_check_max();
 475         ida_check_conv();
 476         ida_check_random();
 477         ida_simple_get_remove_test();
 478
 479         radix_tree_cpu_dead(1);
 480 }
 481
 482 static void *ida_random_fn(void *arg)
 483 {
 484         rcu_register_thread();
 485         ida_check_random();
 486         rcu_unregister_thread();
 487         return NULL;
 488 }
 489
 490 void ida_thread_tests(void)
 491 {
 492         pthread_t threads[10];
 493         int i;
 494
 495         for (i = 0; i < ARRAY_SIZE(threads); i++)
 496                 if (pthread_create(&threads[i], NULL, ida_random_fn, NULL)) {
 497                         perror("creating ida thread");
 498                         exit(1);
 499                 }
 500
 501         while (i--)
 502                 pthread_join(threads[i], NULL);
 503 }
 504
 505 int __weak main(void)
 506 {
 507         radix_tree_init();
 508         idr_checks();
 509         ida_checks();
 510         ida_thread_tests();
 511         radix_tree_cpu_dead(1);
 512         rcu_barrier();
 513         if (nr_allocated)
 514                 printf("nr_allocated = %d\n", nr_allocated);
 515         return 0;
 516 }