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/slab.h>
  24 #include <linux/sched.h>
  25 #include <linux/random.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/wait.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);
  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 };
 103
 104 static struct rhashtable_params test_rht_params_dup = {
 105         .head_offset = offsetof(struct test_obj_rhl, list_node),
 106         .key_offset = offsetof(struct test_obj_rhl, value),
 107         .key_len = sizeof(struct test_obj_val),
 108         .hashfn = jhash,
 109         .obj_hashfn = my_hashfn,
 110         .obj_cmpfn = my_cmpfn,
 111         .nelem_hint = 128,
 112         .automatic_shrinking = false,
 113 };
 114
 115 static atomic_t startup_count;
 116 static DECLARE_WAIT_QUEUE_HEAD(startup_wait);
 117
 118 static int insert_retry(struct rhashtable *ht, struct test_obj *obj,
 119                         const struct rhashtable_params params)
 120 {
 121         int err, retries = -1, enomem_retries = 0;
 122
 123         do {
 124                 retries++;
 125                 cond_resched();
 126                 err = rhashtable_insert_fast(ht, &obj->node, params);
 127                 if (err == -ENOMEM && enomem_retry) {
 128                         enomem_retries++;
 129                         err = -EBUSY;
 130                 }
 131         } while (err == -EBUSY);
 132
 133         if (enomem_retries)
 134                 pr_info(" %u insertions retried after -ENOMEM\n",
 135                         enomem_retries);
 136
 137         return err ? : retries;
 138 }
 139
 140 static int __init test_rht_lookup(struct rhashtable *ht, struct test_obj *array,
 141                                   unsigned int entries)
 142 {
 143         unsigned int i;
 144
 145         for (i = 0; i < entries; i++) {
 146                 struct test_obj *obj;
 147                 bool expected = !(i % 2);
 148                 struct test_obj_val key = {
 149                         .id = i,
 150                 };
 151
 152                 if (array[i / 2].value.id == TEST_INSERT_FAIL)
 153                         expected = false;
 154
 155                 obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
 156
 157                 if (expected && !obj) {
 158                         pr_warn("Test failed: Could not find key %u\n", key.id);
 159                         return -ENOENT;
 160                 } else if (!expected && obj) {
 161                         pr_warn("Test failed: Unexpected entry found for key %u\n",
 162                                 key.id);
 163                         return -EEXIST;
 164                 } else if (expected && obj) {
 165                         if (obj->value.id != i) {
 166                                 pr_warn("Test failed: Lookup value mismatch %u!=%u\n",
 167                                         obj->value.id, i);
 168                                 return -EINVAL;
 169                         }
 170                 }
 171
 172                 cond_resched_rcu();
 173         }
 174
 175         return 0;
 176 }
 177
 178 static void test_bucket_stats(struct rhashtable *ht, unsigned int entries)
 179 {
 180         unsigned int total = 0, chain_len = 0;
 181         struct rhashtable_iter hti;
 182         struct rhash_head *pos;
 183
 184         rhashtable_walk_enter(ht, &hti);
 185         rhashtable_walk_start(&hti);
 186
 187         while ((pos = rhashtable_walk_next(&hti))) {
 188                 if (PTR_ERR(pos) == -EAGAIN) {
 189                         pr_info("Info: encountered resize\n");
 190                         chain_len++;
 191                         continue;
 192                 } else if (IS_ERR(pos)) {
 193                         pr_warn("Test failed: rhashtable_walk_next() error: %ld\n",
 194                                 PTR_ERR(pos));
 195                         break;
 196                 }
 197
 198                 total++;
 199         }
 200
 201         rhashtable_walk_stop(&hti);
 202         rhashtable_walk_exit(&hti);
 203
 204         pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d, table-jumps=%u\n",
 205                 total, atomic_read(&ht->nelems), entries, chain_len);
 206
 207         if (total != atomic_read(&ht->nelems) || total != entries)
 208                 pr_warn("Test failed: Total count mismatch ^^^");
 209 }
 210
 211 static s64 __init test_rhashtable(struct rhashtable *ht, struct test_obj *array,
 212                                   unsigned int entries)
 213 {
 214         struct test_obj *obj;
 215         int err;
 216         unsigned int i, insert_retries = 0;
 217         s64 start, end;
 218
 219         /*
 220          * Insertion Test:
 221          * Insert entries into table with all keys even numbers
 222          */
 223         pr_info("  Adding %d keys\n", entries);
 224         start = ktime_get_ns();
 225         for (i = 0; i < entries; i++) {
 226                 struct test_obj *obj = &array[i];
 227
 228                 obj->value.id = i * 2;
 229                 err = insert_retry(ht, obj, test_rht_params);
 230                 if (err > 0)
 231                         insert_retries += err;
 232                 else if (err)
 233                         return err;
 234         }
 235
 236         if (insert_retries)
 237                 pr_info("  %u insertions retried due to memory pressure\n",
 238                         insert_retries);
 239
 240         test_bucket_stats(ht, entries);
 241         rcu_read_lock();
 242         test_rht_lookup(ht, array, entries);
 243         rcu_read_unlock();
 244
 245         test_bucket_stats(ht, entries);
 246
 247         pr_info("  Deleting %d keys\n", entries);
 248         for (i = 0; i < entries; i++) {
 249                 struct test_obj_val key = {
 250                         .id = i * 2,
 251                 };
 252
 253                 if (array[i].value.id != TEST_INSERT_FAIL) {
 254                         obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
 255                         BUG_ON(!obj);
 256
 257                         rhashtable_remove_fast(ht, &obj->node, test_rht_params);
 258                 }
 259
 260                 cond_resched();
 261         }
 262
 263         end = ktime_get_ns();
 264         pr_info("  Duration of test: %lld ns\n", end - start);
 265
 266         return end - start;
 267 }
 268
 269 static struct rhashtable ht;
 270 static struct rhltable rhlt;
 271
 272 static int __init test_rhltable(unsigned int entries)
 273 {
 274         struct test_obj_rhl *rhl_test_objects;
 275         unsigned long *obj_in_table;
 276         unsigned int i, j, k;
 277         int ret, err;
 278
 279         if (entries == 0)
 280                 entries = 1;
 281
 282         rhl_test_objects = vzalloc(array_size(entries,
 283                                               sizeof(*rhl_test_objects)));
 284         if (!rhl_test_objects)
 285                 return -ENOMEM;
 286
 287         ret = -ENOMEM;
 288         obj_in_table = vzalloc(array_size(sizeof(unsigned long),
 289                                           BITS_TO_LONGS(entries)));
 290         if (!obj_in_table)
 291                 goto out_free;
 292
 293         err = rhltable_init(&rhlt, &test_rht_params);
 294         if (WARN_ON(err))
 295                 goto out_free;
 296
 297         k = prandom_u32();
 298         ret = 0;
 299         for (i = 0; i < entries; i++) {
 300                 rhl_test_objects[i].value.id = k;
 301                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
 302                                       test_rht_params);
 303                 if (WARN(err, "error %d on element %d\n", err, i))
 304                         break;
 305                 if (err == 0)
 306                         set_bit(i, obj_in_table);
 307         }
 308
 309         if (err)
 310                 ret = err;
 311
 312         pr_info("test %d add/delete pairs into rhlist\n", entries);
 313         for (i = 0; i < entries; i++) {
 314                 struct rhlist_head *h, *pos;
 315                 struct test_obj_rhl *obj;
 316                 struct test_obj_val key = {
 317                         .id = k,
 318                 };
 319                 bool found;
 320
 321                 rcu_read_lock();
 322                 h = rhltable_lookup(&rhlt, &key, test_rht_params);
 323                 if (WARN(!h, "key not found during iteration %d of %d", i, entries)) {
 324                         rcu_read_unlock();
 325                         break;
 326                 }
 327
 328                 if (i) {
 329                         j = i - 1;
 330                         rhl_for_each_entry_rcu(obj, pos, h, list_node) {
 331                                 if (WARN(pos == &rhl_test_objects[j].list_node, "old element found, should be gone"))
 332                                         break;
 333                         }
 334                 }
 335
 336                 cond_resched_rcu();
 337
 338                 found = false;
 339
 340                 rhl_for_each_entry_rcu(obj, pos, h, list_node) {
 341                         if (pos == &rhl_test_objects[i].list_node) {
 342                                 found = true;
 343                                 break;
 344                         }
 345                 }
 346
 347                 rcu_read_unlock();
 348
 349                 if (WARN(!found, "element %d not found", i))
 350                         break;
 351
 352                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 353                 WARN(err, "rhltable_remove: err %d for iteration %d\n", err, i);
 354                 if (err == 0)
 355                         clear_bit(i, obj_in_table);
 356         }
 357
 358         if (ret == 0 && err)
 359                 ret = err;
 360
 361         for (i = 0; i < entries; i++) {
 362                 WARN(test_bit(i, obj_in_table), "elem %d allegedly still present", i);
 363
 364                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
 365                                       test_rht_params);
 366                 if (WARN(err, "error %d on element %d\n", err, i))
 367                         break;
 368                 if (err == 0)
 369                         set_bit(i, obj_in_table);
 370         }
 371
 372         pr_info("test %d random rhlist add/delete operations\n", entries);
 373         for (j = 0; j < entries; j++) {
 374                 u32 i = prandom_u32_max(entries);
 375                 u32 prand = prandom_u32();
 376
 377                 cond_resched();
 378
 379                 if (prand == 0)
 380                         prand = prandom_u32();
 381
 382                 if (prand & 1) {
 383                         prand >>= 1;
 384                         continue;
 385                 }
 386
 387                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 388                 if (test_bit(i, obj_in_table)) {
 389                         clear_bit(i, obj_in_table);
 390                         if (WARN(err, "cannot remove element at slot %d", i))
 391                                 continue;
 392                 } else {
 393                         if (WARN(err != -ENOENT, "removed non-existent element %d, error %d not %d",
 394                              i, err, -ENOENT))
 395                                 continue;
 396                 }
 397
 398                 if (prand & 1) {
 399                         prand >>= 1;
 400                         continue;
 401                 }
 402
 403                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 404                 if (err == 0) {
 405                         if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
 406                                 continue;
 407                 } else {
 408                         if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
 409                                 continue;
 410                 }
 411
 412                 if (prand & 1) {
 413                         prand >>= 1;
 414                         continue;
 415                 }
 416
 417                 i = prandom_u32_max(entries);
 418                 if (test_bit(i, obj_in_table)) {
 419                         err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 420                         WARN(err, "cannot remove element at slot %d", i);
 421                         if (err == 0)
 422                                 clear_bit(i, obj_in_table);
 423                 } else {
 424                         err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 425                         WARN(err, "failed to insert object %d", i);
 426                         if (err == 0)
 427                                 set_bit(i, obj_in_table);
 428                 }
 429         }
 430
 431         for (i = 0; i < entries; i++) {
 432                 cond_resched();
 433                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 434                 if (test_bit(i, obj_in_table)) {
 435                         if (WARN(err, "cannot remove element at slot %d", i))
 436                                 continue;
 437                 } else {
 438                         if (WARN(err != -ENOENT, "removed non-existent element, error %d not %d",
 439                                  err, -ENOENT))
 440                         continue;
 441                 }
 442         }
 443
 444         rhltable_destroy(&rhlt);
 445 out_free:
 446         vfree(rhl_test_objects);
 447         vfree(obj_in_table);
 448         return ret;
 449 }
 450
 451 static int __init test_rhashtable_max(struct test_obj *array,
 452                                       unsigned int entries)
 453 {
 454         unsigned int i, insert_retries = 0;
 455         int err;
 456
 457         test_rht_params.max_size = roundup_pow_of_two(entries / 8);
 458         err = rhashtable_init(&ht, &test_rht_params);
 459         if (err)
 460                 return err;
 461
 462         for (i = 0; i < ht.max_elems; i++) {
 463                 struct test_obj *obj = &array[i];
 464
 465                 obj->value.id = i * 2;
 466                 err = insert_retry(&ht, obj, test_rht_params);
 467                 if (err > 0)
 468                         insert_retries += err;
 469                 else if (err)
 470                         return err;
 471         }
 472
 473         err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
 474         if (err == -E2BIG) {
 475                 err = 0;
 476         } else {
 477                 pr_info("insert element %u should have failed with %d, got %d\n",
 478                                 ht.max_elems, -E2BIG, err);
 479                 if (err == 0)
 480                         err = -1;
 481         }
 482
 483         rhashtable_destroy(&ht);
 484
 485         return err;
 486 }
 487
 488 static unsigned int __init print_ht(struct rhltable *rhlt)
 489 {
 490         struct rhashtable *ht;
 491         const struct bucket_table *tbl;
 492         char buff[512] = "";
 493         unsigned int i, cnt = 0;
 494
 495         ht = &rhlt->ht;
 496         /* Take the mutex to avoid RCU warning */
 497         mutex_lock(&ht->mutex);
 498         tbl = rht_dereference(ht->tbl, ht);
 499         for (i = 0; i < tbl->size; i++) {
 500                 struct rhash_head *pos, *next;
 501                 struct test_obj_rhl *p;
 502
 503                 pos = rht_ptr_exclusive(tbl->buckets + i);
 504                 next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
 505
 506                 if (!rht_is_a_nulls(pos)) {
 507                         sprintf(buff, "%s\nbucket[%d] -> ", buff, i);
 508                 }
 509
 510                 while (!rht_is_a_nulls(pos)) {
 511                         struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
 512                         sprintf(buff, "%s[[", buff);
 513                         do {
 514                                 pos = &list->rhead;
 515                                 list = rht_dereference(list->next, ht);
 516                                 p = rht_obj(ht, pos);
 517
 518                                 sprintf(buff, "%s val %d (tid=%d)%s", buff, p->value.id, p->value.tid,
 519                                         list? ", " : " ");
 520                                 cnt++;
 521                         } while (list);
 522
 523                         pos = next,
 524                         next = !rht_is_a_nulls(pos) ?
 525                                 rht_dereference(pos->next, ht) : NULL;
 526
 527                         sprintf(buff, "%s]]%s", buff, !rht_is_a_nulls(pos) ? " -> " : "");
 528                 }
 529         }
 530         printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
 531         mutex_unlock(&ht->mutex);
 532
 533         return cnt;
 534 }
 535
 536 static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
 537                                   int cnt, bool slow)
 538 {
 539         struct rhltable *rhlt;
 540         unsigned int i, ret;
 541         const char *key;
 542         int err = 0;
 543
 544         rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
 545         if (WARN_ON(!rhlt))
 546                 return -EINVAL;
 547
 548         err = rhltable_init(rhlt, &test_rht_params_dup);
 549         if (WARN_ON(err)) {
 550                 kfree(rhlt);
 551                 return err;
 552         }
 553
 554         for (i = 0; i < cnt; i++) {
 555                 rhl_test_objects[i].value.tid = i;
 556                 key = rht_obj(&rhlt->ht, &rhl_test_objects[i].list_node.rhead);
 557                 key += test_rht_params_dup.key_offset;
 558
 559                 if (slow) {
 560                         err = PTR_ERR(rhashtable_insert_slow(&rhlt->ht, key,
 561                                                              &rhl_test_objects[i].list_node.rhead));
 562                         if (err == -EAGAIN)
 563                                 err = 0;
 564                 } else
 565                         err = rhltable_insert(rhlt,
 566                                               &rhl_test_objects[i].list_node,
 567                                               test_rht_params_dup);
 568                 if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
 569                         goto skip_print;
 570         }
 571
 572         ret = print_ht(rhlt);
 573         WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
 574
 575 skip_print:
 576         rhltable_destroy(rhlt);
 577         kfree(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         if (atomic_dec_and_test(&startup_count))
 640                 wake_up(&startup_wait);
 641         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == -1)) {
 642                 pr_err("  thread[%d]: interrupted\n", tdata->id);
 643                 goto out;
 644         }
 645
 646         for (i = 0; i < tdata->entries; i++) {
 647                 tdata->objs[i].value.id = i;
 648                 tdata->objs[i].value.tid = tdata->id;
 649                 err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
 650                 if (err > 0) {
 651                         insert_retries += err;
 652                 } else if (err) {
 653                         pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
 654                                tdata->id);
 655                         goto out;
 656                 }
 657         }
 658         if (insert_retries)
 659                 pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
 660                         tdata->id, insert_retries);
 661
 662         err = thread_lookup_test(tdata);
 663         if (err) {
 664                 pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
 665                        tdata->id);
 666                 goto out;
 667         }
 668
 669         for (step = 10; step > 0; step--) {
 670                 for (i = 0; i < tdata->entries; i += step) {
 671                         if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
 672                                 continue;
 673                         err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
 674                                                      test_rht_params);
 675                         if (err) {
 676                                 pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
 677                                        tdata->id);
 678                                 goto out;
 679                         }
 680                         tdata->objs[i].value.id = TEST_INSERT_FAIL;
 681
 682                         cond_resched();
 683                 }
 684                 err = thread_lookup_test(tdata);
 685                 if (err) {
 686                         pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
 687                                tdata->id);
 688                         goto out;
 689                 }
 690         }
 691 out:
 692         while (!kthread_should_stop()) {
 693                 set_current_state(TASK_INTERRUPTIBLE);
 694                 schedule();
 695         }
 696         return err;
 697 }
 698
 699 static int __init test_rht_init(void)
 700 {
 701         unsigned int entries;
 702         int i, err, started_threads = 0, failed_threads = 0;
 703         u64 total_time = 0;
 704         struct thread_data *tdata;
 705         struct test_obj *objs;
 706
 707         if (parm_entries < 0)
 708                 parm_entries = 1;
 709
 710         entries = min(parm_entries, MAX_ENTRIES);
 711
 712         test_rht_params.automatic_shrinking = shrinking;
 713         test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
 714         test_rht_params.nelem_hint = size;
 715
 716         objs = vzalloc(array_size(sizeof(struct test_obj),
 717                                   test_rht_params.max_size + 1));
 718         if (!objs)
 719                 return -ENOMEM;
 720
 721         pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
 722                 size, max_size, shrinking);
 723
 724         for (i = 0; i < runs; i++) {
 725                 s64 time;
 726
 727                 pr_info("Test %02d:\n", i);
 728                 memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
 729
 730                 err = rhashtable_init(&ht, &test_rht_params);
 731                 if (err < 0) {
 732                         pr_warn("Test failed: Unable to initialize hashtable: %d\n",
 733                                 err);
 734                         continue;
 735                 }
 736
 737                 time = test_rhashtable(&ht, objs, entries);
 738                 rhashtable_destroy(&ht);
 739                 if (time < 0) {
 740                         vfree(objs);
 741                         pr_warn("Test failed: return code %lld\n", time);
 742                         return -EINVAL;
 743                 }
 744
 745                 total_time += time;
 746         }
 747
 748         pr_info("test if its possible to exceed max_size %d: %s\n",
 749                         test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
 750                         "no, ok" : "YES, failed");
 751         vfree(objs);
 752
 753         do_div(total_time, runs);
 754         pr_info("Average test time: %llu\n", total_time);
 755
 756         test_insert_duplicates_run();
 757
 758         if (!tcount)
 759                 return 0;
 760
 761         pr_info("Testing concurrent rhashtable access from %d threads\n",
 762                 tcount);
 763         atomic_set(&startup_count, tcount);
 764         tdata = vzalloc(array_size(tcount, sizeof(struct thread_data)));
 765         if (!tdata)
 766                 return -ENOMEM;
 767         objs  = vzalloc(array3_size(sizeof(struct test_obj), tcount, entries));
 768         if (!objs) {
 769                 vfree(tdata);
 770                 return -ENOMEM;
 771         }
 772
 773         test_rht_params.max_size = max_size ? :
 774                                    roundup_pow_of_two(tcount * entries);
 775         err = rhashtable_init(&ht, &test_rht_params);
 776         if (err < 0) {
 777                 pr_warn("Test failed: Unable to initialize hashtable: %d\n",
 778                         err);
 779                 vfree(tdata);
 780                 vfree(objs);
 781                 return -EINVAL;
 782         }
 783         for (i = 0; i < tcount; i++) {
 784                 tdata[i].id = i;
 785                 tdata[i].entries = entries;
 786                 tdata[i].objs = objs + i * entries;
 787                 tdata[i].task = kthread_run(threadfunc, &tdata[i],
 788                                             "rhashtable_thrad[%d]", i);
 789                 if (IS_ERR(tdata[i].task)) {
 790                         pr_err(" kthread_run failed for thread %d\n", i);
 791                         atomic_dec(&startup_count);
 792                 } else {
 793                         started_threads++;
 794                 }
 795         }
 796         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == 0))
 797                 pr_err("  wait_event interruptible failed\n");
 798         /* count is 0 now, set it to -1 and wake up all threads together */
 799         atomic_dec(&startup_count);
 800         wake_up_all(&startup_wait);
 801         for (i = 0; i < tcount; i++) {
 802                 if (IS_ERR(tdata[i].task))
 803                         continue;
 804                 if ((err = kthread_stop(tdata[i].task))) {
 805                         pr_warn("Test failed: thread %d returned: %d\n",
 806                                 i, err);
 807                         failed_threads++;
 808                 }
 809         }
 810         rhashtable_destroy(&ht);
 811         vfree(tdata);
 812         vfree(objs);
 813
 814         /*
 815          * rhltable_remove is very expensive, default values can cause test
 816          * to run for 2 minutes or more,  use a smaller number instead.
 817          */
 818         err = test_rhltable(entries / 16);
 819         pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
 820                 started_threads, failed_threads, err);
 821         return 0;
 822 }
 823
 824 static void __exit test_rht_exit(void)
 825 {
 826 }
 827
 828 module_init(test_rht_init);
 829 module_exit(test_rht_exit);
 830
 831 MODULE_LICENSE("GPL v2");