lib/test_rhashtable.c

   1 /*
   2  * Resizable, Scalable, Concurrent Hash Table
   3  *
   4  * Copyright (c) 2014-2015 Thomas Graf <tgraf@suug.ch>
   5  * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 /**************************************************************************
  13  * Self Test
  14  **************************************************************************/
  15
  16 #include <linux/init.h>
  17 #include <linux/jhash.h>
  18 #include <linux/kernel.h>
  19 #include <linux/kthread.h>
  20 #include <linux/module.h>
  21 #include <linux/rcupdate.h>
  22 #include <linux/rhashtable.h>
  23 #include <linux/semaphore.h>
  24 #include <linux/slab.h>
  25 #include <linux/sched.h>
  26 #include <linux/random.h>
  27 #include <linux/vmalloc.h>
  28
  29 #define MAX_ENTRIES     1000000
  30 #define TEST_INSERT_FAIL INT_MAX
  31
  32 static int parm_entries = 50000;
  33 module_param(parm_entries, int, 0);
  34 MODULE_PARM_DESC(parm_entries, "Number of entries to add (default: 50000)");
  35
  36 static int runs = 4;
  37 module_param(runs, int, 0);
  38 MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)");
  39
  40 static int max_size = 0;
  41 module_param(max_size, int, 0);
  42 MODULE_PARM_DESC(max_size, "Maximum table size (default: calculated)");
  43
  44 static bool shrinking = false;
  45 module_param(shrinking, bool, 0);
  46 MODULE_PARM_DESC(shrinking, "Enable automatic shrinking (default: off)");
  47
  48 static int size = 8;
  49 module_param(size, int, 0);
  50 MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)");
  51
  52 static int tcount = 10;
  53 module_param(tcount, int, 0);
  54 MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");
  55
  56 static bool enomem_retry = false;
  57 module_param(enomem_retry, bool, 0);
  58 MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");
  59
  60 struct test_obj_val {
  61         int     id;
  62         int     tid;
  63 };
  64
  65 struct test_obj {
  66         struct test_obj_val     value;
  67         struct rhash_head       node;
  68 };
  69
  70 struct test_obj_rhl {
  71         struct test_obj_val     value;
  72         struct rhlist_head      list_node;
  73 };
  74
  75 struct thread_data {
  76         unsigned int entries;
  77         int id;
  78         struct task_struct *task;
  79         struct test_obj *objs;
  80 };
  81
  82 static u32 my_hashfn(const void *data, u32 len, u32 seed)
  83 {
  84         const struct test_obj_rhl *obj = data;
  85
  86         return (obj->value.id % 10) << RHT_HASH_RESERVED_SPACE;
  87 }
  88
  89 static int my_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
  90 {
  91         const struct test_obj_rhl *test_obj = obj;
  92         const struct test_obj_val *val = arg->key;
  93
  94         return test_obj->value.id - val->id;
  95 }
  96
  97 static struct rhashtable_params test_rht_params = {
  98         .head_offset = offsetof(struct test_obj, node),
  99         .key_offset = offsetof(struct test_obj, value),
 100         .key_len = sizeof(struct test_obj_val),
 101         .hashfn = jhash,
 102         .nulls_base = (3U << RHT_BASE_SHIFT),
 103 };
 104
 105 static struct rhashtable_params test_rht_params_dup = {
 106         .head_offset = offsetof(struct test_obj_rhl, list_node),
 107         .key_offset = offsetof(struct test_obj_rhl, value),
 108         .key_len = sizeof(struct test_obj_val),
 109         .hashfn = jhash,
 110         .obj_hashfn = my_hashfn,
 111         .obj_cmpfn = my_cmpfn,
 112         .nelem_hint = 128,
 113         .automatic_shrinking = false,
 114 };
 115
 116 static struct semaphore prestart_sem;
 117 static struct semaphore startup_sem = __SEMAPHORE_INITIALIZER(startup_sem, 0);
 118
 119 static int insert_retry(struct rhashtable *ht, struct test_obj *obj,
 120                         const struct rhashtable_params params)
 121 {
 122         int err, retries = -1, enomem_retries = 0;
 123
 124         do {
 125                 retries++;
 126                 cond_resched();
 127                 err = rhashtable_insert_fast(ht, &obj->node, params);
 128                 if (err == -ENOMEM && enomem_retry) {
 129                         enomem_retries++;
 130                         err = -EBUSY;
 131                 }
 132         } while (err == -EBUSY);
 133
 134         if (enomem_retries)
 135                 pr_info(" %u insertions retried after -ENOMEM\n",
 136                         enomem_retries);
 137
 138         return err ? : retries;
 139 }
 140
 141 static int __init test_rht_lookup(struct rhashtable *ht, struct test_obj *array,
 142                                   unsigned int entries)
 143 {
 144         unsigned int i;
 145
 146         for (i = 0; i < entries; i++) {
 147                 struct test_obj *obj;
 148                 bool expected = !(i % 2);
 149                 struct test_obj_val key = {
 150                         .id = i,
 151                 };
 152
 153                 if (array[i / 2].value.id == TEST_INSERT_FAIL)
 154                         expected = false;
 155
 156                 obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
 157
 158                 if (expected && !obj) {
 159                         pr_warn("Test failed: Could not find key %u\n", key.id);
 160                         return -ENOENT;
 161                 } else if (!expected && obj) {
 162                         pr_warn("Test failed: Unexpected entry found for key %u\n",
 163                                 key.id);
 164                         return -EEXIST;
 165                 } else if (expected && obj) {
 166                         if (obj->value.id != i) {
 167                                 pr_warn("Test failed: Lookup value mismatch %u!=%u\n",
 168                                         obj->value.id, i);
 169                                 return -EINVAL;
 170                         }
 171                 }
 172
 173                 cond_resched_rcu();
 174         }
 175
 176         return 0;
 177 }
 178
 179 static void test_bucket_stats(struct rhashtable *ht, unsigned int entries)
 180 {
 181         unsigned int err, total = 0, chain_len = 0;
 182         struct rhashtable_iter hti;
 183         struct rhash_head *pos;
 184
 185         err = rhashtable_walk_init(ht, &hti, GFP_KERNEL);
 186         if (err) {
 187                 pr_warn("Test failed: allocation error");
 188                 return;
 189         }
 190
 191         err = rhashtable_walk_start(&hti);
 192         if (err && err != -EAGAIN) {
 193                 pr_warn("Test failed: iterator failed: %d\n", err);
 194                 return;
 195         }
 196
 197         while ((pos = rhashtable_walk_next(&hti))) {
 198                 if (PTR_ERR(pos) == -EAGAIN) {
 199                         pr_info("Info: encountered resize\n");
 200                         chain_len++;
 201                         continue;
 202                 } else if (IS_ERR(pos)) {
 203                         pr_warn("Test failed: rhashtable_walk_next() error: %ld\n",
 204                                 PTR_ERR(pos));
 205                         break;
 206                 }
 207
 208                 total++;
 209         }
 210
 211         rhashtable_walk_stop(&hti);
 212         rhashtable_walk_exit(&hti);
 213
 214         pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d, table-jumps=%u\n",
 215                 total, atomic_read(&ht->nelems), entries, chain_len);
 216
 217         if (total != atomic_read(&ht->nelems) || total != entries)
 218                 pr_warn("Test failed: Total count mismatch ^^^");
 219 }
 220
 221 static s64 __init test_rhashtable(struct rhashtable *ht, struct test_obj *array,
 222                                   unsigned int entries)
 223 {
 224         struct test_obj *obj;
 225         int err;
 226         unsigned int i, insert_retries = 0;
 227         s64 start, end;
 228
 229         /*
 230          * Insertion Test:
 231          * Insert entries into table with all keys even numbers
 232          */
 233         pr_info("  Adding %d keys\n", entries);
 234         start = ktime_get_ns();
 235         for (i = 0; i < entries; i++) {
 236                 struct test_obj *obj = &array[i];
 237
 238                 obj->value.id = i * 2;
 239                 err = insert_retry(ht, obj, test_rht_params);
 240                 if (err > 0)
 241                         insert_retries += err;
 242                 else if (err)
 243                         return err;
 244         }
 245
 246         if (insert_retries)
 247                 pr_info("  %u insertions retried due to memory pressure\n",
 248                         insert_retries);
 249
 250         test_bucket_stats(ht, entries);
 251         rcu_read_lock();
 252         test_rht_lookup(ht, array, entries);
 253         rcu_read_unlock();
 254
 255         test_bucket_stats(ht, entries);
 256
 257         pr_info("  Deleting %d keys\n", entries);
 258         for (i = 0; i < entries; i++) {
 259                 struct test_obj_val key = {
 260                         .id = i * 2,
 261                 };
 262
 263                 if (array[i].value.id != TEST_INSERT_FAIL) {
 264                         obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
 265                         BUG_ON(!obj);
 266
 267                         rhashtable_remove_fast(ht, &obj->node, test_rht_params);
 268                 }
 269
 270                 cond_resched();
 271         }
 272
 273         end = ktime_get_ns();
 274         pr_info("  Duration of test: %lld ns\n", end - start);
 275
 276         return end - start;
 277 }
 278
 279 static struct rhashtable ht;
 280 static struct rhltable rhlt;
 281
 282 static int __init test_rhltable(unsigned int entries)
 283 {
 284         struct test_obj_rhl *rhl_test_objects;
 285         unsigned long *obj_in_table;
 286         unsigned int i, j, k;
 287         int ret, err;
 288
 289         if (entries == 0)
 290                 entries = 1;
 291
 292         rhl_test_objects = vzalloc(sizeof(*rhl_test_objects) * entries);
 293         if (!rhl_test_objects)
 294                 return -ENOMEM;
 295
 296         ret = -ENOMEM;
 297         obj_in_table = vzalloc(BITS_TO_LONGS(entries) * sizeof(unsigned long));
 298         if (!obj_in_table)
 299                 goto out_free;
 300
 301         /* nulls_base not supported in rhlist interface */
 302         test_rht_params.nulls_base = 0;
 303         err = rhltable_init(&rhlt, &test_rht_params);
 304         if (WARN_ON(err))
 305                 goto out_free;
 306
 307         k = prandom_u32();
 308         ret = 0;
 309         for (i = 0; i < entries; i++) {
 310                 rhl_test_objects[i].value.id = k;
 311                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
 312                                       test_rht_params);
 313                 if (WARN(err, "error %d on element %d\n", err, i))
 314                         break;
 315                 if (err == 0)
 316                         set_bit(i, obj_in_table);
 317         }
 318
 319         if (err)
 320                 ret = err;
 321
 322         pr_info("test %d add/delete pairs into rhlist\n", entries);
 323         for (i = 0; i < entries; i++) {
 324                 struct rhlist_head *h, *pos;
 325                 struct test_obj_rhl *obj;
 326                 struct test_obj_val key = {
 327                         .id = k,
 328                 };
 329                 bool found;
 330
 331                 rcu_read_lock();
 332                 h = rhltable_lookup(&rhlt, &key, test_rht_params);
 333                 if (WARN(!h, "key not found during iteration %d of %d", i, entries)) {
 334                         rcu_read_unlock();
 335                         break;
 336                 }
 337
 338                 if (i) {
 339                         j = i - 1;
 340                         rhl_for_each_entry_rcu(obj, pos, h, list_node) {
 341                                 if (WARN(pos == &rhl_test_objects[j].list_node, "old element found, should be gone"))
 342                                         break;
 343                         }
 344                 }
 345
 346                 cond_resched_rcu();
 347
 348                 found = false;
 349
 350                 rhl_for_each_entry_rcu(obj, pos, h, list_node) {
 351                         if (pos == &rhl_test_objects[i].list_node) {
 352                                 found = true;
 353                                 break;
 354                         }
 355                 }
 356
 357                 rcu_read_unlock();
 358
 359                 if (WARN(!found, "element %d not found", i))
 360                         break;
 361
 362                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 363                 WARN(err, "rhltable_remove: err %d for iteration %d\n", err, i);
 364                 if (err == 0)
 365                         clear_bit(i, obj_in_table);
 366         }
 367
 368         if (ret == 0 && err)
 369                 ret = err;
 370
 371         for (i = 0; i < entries; i++) {
 372                 WARN(test_bit(i, obj_in_table), "elem %d allegedly still present", i);
 373
 374                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
 375                                       test_rht_params);
 376                 if (WARN(err, "error %d on element %d\n", err, i))
 377                         break;
 378                 if (err == 0)
 379                         set_bit(i, obj_in_table);
 380         }
 381
 382         pr_info("test %d random rhlist add/delete operations\n", entries);
 383         for (j = 0; j < entries; j++) {
 384                 u32 i = prandom_u32_max(entries);
 385                 u32 prand = prandom_u32();
 386
 387                 cond_resched();
 388
 389                 if (prand == 0)
 390                         prand = prandom_u32();
 391
 392                 if (prand & 1) {
 393                         prand >>= 1;
 394                         continue;
 395                 }
 396
 397                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 398                 if (test_bit(i, obj_in_table)) {
 399                         clear_bit(i, obj_in_table);
 400                         if (WARN(err, "cannot remove element at slot %d", i))
 401                                 continue;
 402                 } else {
 403                         if (WARN(err != -ENOENT, "removed non-existant element %d, error %d not %d",
 404                              i, err, -ENOENT))
 405                                 continue;
 406                 }
 407
 408                 if (prand & 1) {
 409                         prand >>= 1;
 410                         continue;
 411                 }
 412
 413                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 414                 if (err == 0) {
 415                         if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
 416                                 continue;
 417                 } else {
 418                         if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
 419                                 continue;
 420                 }
 421
 422                 if (prand & 1) {
 423                         prand >>= 1;
 424                         continue;
 425                 }
 426
 427                 i = prandom_u32_max(entries);
 428                 if (test_bit(i, obj_in_table)) {
 429                         err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 430                         WARN(err, "cannot remove element at slot %d", i);
 431                         if (err == 0)
 432                                 clear_bit(i, obj_in_table);
 433                 } else {
 434                         err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 435                         WARN(err, "failed to insert object %d", i);
 436                         if (err == 0)
 437                                 set_bit(i, obj_in_table);
 438                 }
 439         }
 440
 441         for (i = 0; i < entries; i++) {
 442                 cond_resched();
 443                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 444                 if (test_bit(i, obj_in_table)) {
 445                         if (WARN(err, "cannot remove element at slot %d", i))
 446                                 continue;
 447                 } else {
 448                         if (WARN(err != -ENOENT, "removed non-existant element, error %d not %d",
 449                                  err, -ENOENT))
 450                         continue;
 451                 }
 452         }
 453
 454         rhltable_destroy(&rhlt);
 455 out_free:
 456         vfree(rhl_test_objects);
 457         vfree(obj_in_table);
 458         return ret;
 459 }
 460
 461 static int __init test_rhashtable_max(struct test_obj *array,
 462                                       unsigned int entries)
 463 {
 464         unsigned int i, insert_retries = 0;
 465         int err;
 466
 467         test_rht_params.max_size = roundup_pow_of_two(entries / 8);
 468         err = rhashtable_init(&ht, &test_rht_params);
 469         if (err)
 470                 return err;
 471
 472         for (i = 0; i < ht.max_elems; i++) {
 473                 struct test_obj *obj = &array[i];
 474
 475                 obj->value.id = i * 2;
 476                 err = insert_retry(&ht, obj, test_rht_params);
 477                 if (err > 0)
 478                         insert_retries += err;
 479                 else if (err)
 480                         return err;
 481         }
 482
 483         err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
 484         if (err == -E2BIG) {
 485                 err = 0;
 486         } else {
 487                 pr_info("insert element %u should have failed with %d, got %d\n",
 488                                 ht.max_elems, -E2BIG, err);
 489                 if (err == 0)
 490                         err = -1;
 491         }
 492
 493         rhashtable_destroy(&ht);
 494
 495         return err;
 496 }
 497
 498 static unsigned int __init print_ht(struct rhltable *rhlt)
 499 {
 500         struct rhashtable *ht;
 501         const struct bucket_table *tbl;
 502         char buff[512] = "";
 503         unsigned int i, cnt = 0;
 504
 505         ht = &rhlt->ht;
 506         tbl = rht_dereference(ht->tbl, ht);
 507         for (i = 0; i < tbl->size; i++) {
 508                 struct rhash_head *pos, *next;
 509                 struct test_obj_rhl *p;
 510
 511                 pos = rht_dereference(tbl->buckets[i], ht);
 512                 next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
 513
 514                 if (!rht_is_a_nulls(pos)) {
 515                         sprintf(buff, "%s\nbucket[%d] -> ", buff, i);
 516                 }
 517
 518                 while (!rht_is_a_nulls(pos)) {
 519                         struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
 520                         sprintf(buff, "%s[[", buff);
 521                         do {
 522                                 pos = &list->rhead;
 523                                 list = rht_dereference(list->next, ht);
 524                                 p = rht_obj(ht, pos);
 525
 526                                 sprintf(buff, "%s val %d (tid=%d)%s", buff, p->value.id, p->value.tid,
 527                                         list? ", " : " ");
 528                                 cnt++;
 529                         } while (list);
 530
 531                         pos = next,
 532                         next = !rht_is_a_nulls(pos) ?
 533                                 rht_dereference(pos->next, ht) : NULL;
 534
 535                         sprintf(buff, "%s]]%s", buff, !rht_is_a_nulls(pos) ? " -> " : "");
 536                 }
 537         }
 538         printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
 539
 540         return cnt;
 541 }
 542
 543 static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
 544                                   int cnt, bool slow)
 545 {
 546         struct rhltable rhlt;
 547         unsigned int i, ret;
 548         const char *key;
 549         int err = 0;
 550
 551         err = rhltable_init(&rhlt, &test_rht_params_dup);
 552         if (WARN_ON(err))
 553                 return err;
 554
 555         for (i = 0; i < cnt; i++) {
 556                 rhl_test_objects[i].value.tid = i;
 557                 key = rht_obj(&rhlt.ht, &rhl_test_objects[i].list_node.rhead);
 558                 key += test_rht_params_dup.key_offset;
 559
 560                 if (slow) {
 561                         err = PTR_ERR(rhashtable_insert_slow(&rhlt.ht, key,
 562                                                              &rhl_test_objects[i].list_node.rhead));
 563                         if (err == -EAGAIN)
 564                                 err = 0;
 565                 } else
 566                         err = rhltable_insert(&rhlt,
 567                                               &rhl_test_objects[i].list_node,
 568                                               test_rht_params_dup);
 569                 if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
 570                         goto skip_print;
 571         }
 572
 573         ret = print_ht(&rhlt);
 574         WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
 575
 576 skip_print:
 577         rhltable_destroy(&rhlt);
 578
 579         return 0;
 580 }
 581
 582 static int __init test_insert_duplicates_run(void)
 583 {
 584         struct test_obj_rhl rhl_test_objects[3] = {};
 585
 586         pr_info("test inserting duplicates\n");
 587
 588         /* two different values that map to same bucket */
 589         rhl_test_objects[0].value.id = 1;
 590         rhl_test_objects[1].value.id = 21;
 591
 592         /* and another duplicate with same as [0] value
 593          * which will be second on the bucket list */
 594         rhl_test_objects[2].value.id = rhl_test_objects[0].value.id;
 595
 596         test_insert_dup(rhl_test_objects, 2, false);
 597         test_insert_dup(rhl_test_objects, 3, false);
 598         test_insert_dup(rhl_test_objects, 2, true);
 599         test_insert_dup(rhl_test_objects, 3, true);
 600
 601         return 0;
 602 }
 603
 604 static int thread_lookup_test(struct thread_data *tdata)
 605 {
 606         unsigned int entries = tdata->entries;
 607         int i, err = 0;
 608
 609         for (i = 0; i < entries; i++) {
 610                 struct test_obj *obj;
 611                 struct test_obj_val key = {
 612                         .id = i,
 613                         .tid = tdata->id,
 614                 };
 615
 616                 obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
 617                 if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
 618                         pr_err("  found unexpected object %d-%d\n", key.tid, key.id);
 619                         err++;
 620                 } else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
 621                         pr_err("  object %d-%d not found!\n", key.tid, key.id);
 622                         err++;
 623                 } else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
 624                         pr_err("  wrong object returned (got %d-%d, expected %d-%d)\n",
 625                                obj->value.tid, obj->value.id, key.tid, key.id);
 626                         err++;
 627                 }
 628
 629                 cond_resched();
 630         }
 631         return err;
 632 }
 633
 634 static int threadfunc(void *data)
 635 {
 636         int i, step, err = 0, insert_retries = 0;
 637         struct thread_data *tdata = data;
 638
 639         up(&prestart_sem);
 640         if (down_interruptible(&startup_sem))
 641                 pr_err("  thread[%d]: down_interruptible failed\n", tdata->id);
 642
 643         for (i = 0; i < tdata->entries; i++) {
 644                 tdata->objs[i].value.id = i;
 645                 tdata->objs[i].value.tid = tdata->id;
 646                 err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
 647                 if (err > 0) {
 648                         insert_retries += err;
 649                 } else if (err) {
 650                         pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
 651                                tdata->id);
 652                         goto out;
 653                 }
 654         }
 655         if (insert_retries)
 656                 pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
 657                         tdata->id, insert_retries);
 658
 659         err = thread_lookup_test(tdata);
 660         if (err) {
 661                 pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
 662                        tdata->id);
 663                 goto out;
 664         }
 665
 666         for (step = 10; step > 0; step--) {
 667                 for (i = 0; i < tdata->entries; i += step) {
 668                         if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
 669                                 continue;
 670                         err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
 671                                                      test_rht_params);
 672                         if (err) {
 673                                 pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
 674                                        tdata->id);
 675                                 goto out;
 676                         }
 677                         tdata->objs[i].value.id = TEST_INSERT_FAIL;
 678
 679                         cond_resched();
 680                 }
 681                 err = thread_lookup_test(tdata);
 682                 if (err) {
 683                         pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
 684                                tdata->id);
 685                         goto out;
 686                 }
 687         }
 688 out:
 689         while (!kthread_should_stop()) {
 690                 set_current_state(TASK_INTERRUPTIBLE);
 691                 schedule();
 692         }
 693         return err;
 694 }
 695
 696 static int __init test_rht_init(void)
 697 {
 698         unsigned int entries;
 699         int i, err, started_threads = 0, failed_threads = 0;
 700         u64 total_time = 0;
 701         struct thread_data *tdata;
 702         struct test_obj *objs;
 703
 704         if (parm_entries < 0)
 705                 parm_entries = 1;
 706
 707         entries = min(parm_entries, MAX_ENTRIES);
 708
 709         test_rht_params.automatic_shrinking = shrinking;
 710         test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
 711         test_rht_params.nelem_hint = size;
 712
 713         objs = vzalloc((test_rht_params.max_size + 1) * sizeof(struct test_obj));
 714         if (!objs)
 715                 return -ENOMEM;
 716
 717         pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
 718                 size, max_size, shrinking);
 719
 720         for (i = 0; i < runs; i++) {
 721                 s64 time;
 722
 723                 pr_info("Test %02d:\n", i);
 724                 memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
 725
 726                 err = rhashtable_init(&ht, &test_rht_params);
 727                 if (err < 0) {
 728                         pr_warn("Test failed: Unable to initialize hashtable: %d\n",
 729                                 err);
 730                         continue;
 731                 }
 732
 733                 time = test_rhashtable(&ht, objs, entries);
 734                 rhashtable_destroy(&ht);
 735                 if (time < 0) {
 736                         vfree(objs);
 737                         pr_warn("Test failed: return code %lld\n", time);
 738                         return -EINVAL;
 739                 }
 740
 741                 total_time += time;
 742         }
 743
 744         pr_info("test if its possible to exceed max_size %d: %s\n",
 745                         test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
 746                         "no, ok" : "YES, failed");
 747         vfree(objs);
 748
 749         do_div(total_time, runs);
 750         pr_info("Average test time: %llu\n", total_time);
 751
 752         test_insert_duplicates_run();
 753
 754         if (!tcount)
 755                 return 0;
 756
 757         pr_info("Testing concurrent rhashtable access from %d threads\n",
 758                 tcount);
 759         sema_init(&prestart_sem, 1 - tcount);
 760         tdata = vzalloc(tcount * sizeof(struct thread_data));
 761         if (!tdata)
 762                 return -ENOMEM;
 763         objs  = vzalloc(tcount * entries * sizeof(struct test_obj));
 764         if (!objs) {
 765                 vfree(tdata);
 766                 return -ENOMEM;
 767         }
 768
 769         test_rht_params.max_size = max_size ? :
 770                                    roundup_pow_of_two(tcount * entries);
 771         err = rhashtable_init(&ht, &test_rht_params);
 772         if (err < 0) {
 773                 pr_warn("Test failed: Unable to initialize hashtable: %d\n",
 774                         err);
 775                 vfree(tdata);
 776                 vfree(objs);
 777                 return -EINVAL;
 778         }
 779         for (i = 0; i < tcount; i++) {
 780                 tdata[i].id = i;
 781                 tdata[i].entries = entries;
 782                 tdata[i].objs = objs + i * entries;
 783                 tdata[i].task = kthread_run(threadfunc, &tdata[i],
 784                                             "rhashtable_thrad[%d]", i);
 785                 if (IS_ERR(tdata[i].task))
 786                         pr_err(" kthread_run failed for thread %d\n", i);
 787                 else
 788                         started_threads++;
 789         }
 790         if (down_interruptible(&prestart_sem))
 791                 pr_err("  down interruptible failed\n");
 792         for (i = 0; i < tcount; i++)
 793                 up(&startup_sem);
 794         for (i = 0; i < tcount; i++) {
 795                 if (IS_ERR(tdata[i].task))
 796                         continue;
 797                 if ((err = kthread_stop(tdata[i].task))) {
 798                         pr_warn("Test failed: thread %d returned: %d\n",
 799                                 i, err);
 800                         failed_threads++;
 801                 }
 802         }
 803         rhashtable_destroy(&ht);
 804         vfree(tdata);
 805         vfree(objs);
 806
 807         /*
 808          * rhltable_remove is very expensive, default values can cause test
 809          * to run for 2 minutes or more,  use a smaller number instead.
 810          */
 811         err = test_rhltable(entries / 16);
 812         pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
 813                 started_threads, failed_threads, err);
 814         return 0;
 815 }
 816
 817 static void __exit test_rht_exit(void)
 818 {
 819 }
 820
 821 module_init(test_rht_init);
 822 module_exit(test_rht_exit);
 823
 824 MODULE_LICENSE("GPL v2");