lib/test_rhashtable.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Resizable, Scalable, Concurrent Hash Table
   4  *
   5  * Copyright (c) 2014-2015 Thomas Graf <[email protected]>
   6  * Copyright (c) 2008-2014 Patrick McHardy <[email protected]>
   7  */
   8
   9 /**************************************************************************
  10  * Self Test
  11  **************************************************************************/
  12
  13 #include <linux/init.h>
  14 #include <linux/jhash.h>
  15 #include <linux/kernel.h>
  16 #include <linux/kthread.h>
  17 #include <linux/module.h>
  18 #include <linux/rcupdate.h>
  19 #include <linux/rcupdate_wait.h>
  20 #include <linux/rhashtable.h>
  21 #include <linux/slab.h>
  22 #include <linux/sched.h>
  23 #include <linux/random.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/wait.h>
  26
  27 #define MAX_ENTRIES     1000000
  28 #define TEST_INSERT_FAIL INT_MAX
  29
  30 static int parm_entries = 50000;
  31 module_param(parm_entries, int, 0);
  32 MODULE_PARM_DESC(parm_entries, "Number of entries to add (default: 50000)");
  33
  34 static int runs = 4;
  35 module_param(runs, int, 0);
  36 MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)");
  37
  38 static int max_size = 0;
  39 module_param(max_size, int, 0);
  40 MODULE_PARM_DESC(max_size, "Maximum table size (default: calculated)");
  41
  42 static bool shrinking = false;
  43 module_param(shrinking, bool, 0);
  44 MODULE_PARM_DESC(shrinking, "Enable automatic shrinking (default: off)");
  45
  46 static int size = 8;
  47 module_param(size, int, 0);
  48 MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)");
  49
  50 static int tcount = 10;
  51 module_param(tcount, int, 0);
  52 MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");
  53
  54 static bool enomem_retry = false;
  55 module_param(enomem_retry, bool, 0);
  56 MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");
  57
  58 struct test_obj_val {
  59         int     id;
  60         int     tid;
  61 };
  62
  63 struct test_obj {
  64         struct test_obj_val     value;
  65         struct rhash_head       node;
  66 };
  67
  68 struct test_obj_rhl {
  69         struct test_obj_val     value;
  70         struct rhlist_head      list_node;
  71 };
  72
  73 struct thread_data {
  74         unsigned int entries;
  75         int id;
  76         struct task_struct *task;
  77         struct test_obj *objs;
  78 };
  79
  80 static u32 my_hashfn(const void *data, u32 len, u32 seed)
  81 {
  82         const struct test_obj_rhl *obj = data;
  83
  84         return (obj->value.id % 10);
  85 }
  86
  87 static int my_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
  88 {
  89         const struct test_obj_rhl *test_obj = obj;
  90         const struct test_obj_val *val = arg->key;
  91
  92         return test_obj->value.id - val->id;
  93 }
  94
  95 static struct rhashtable_params test_rht_params = {
  96         .head_offset = offsetof(struct test_obj, node),
  97         .key_offset = offsetof(struct test_obj, value),
  98         .key_len = sizeof(struct test_obj_val),
  99         .hashfn = jhash,
 100 };
 101
 102 static struct rhashtable_params test_rht_params_dup = {
 103         .head_offset = offsetof(struct test_obj_rhl, list_node),
 104         .key_offset = offsetof(struct test_obj_rhl, value),
 105         .key_len = sizeof(struct test_obj_val),
 106         .hashfn = jhash,
 107         .obj_hashfn = my_hashfn,
 108         .obj_cmpfn = my_cmpfn,
 109         .nelem_hint = 128,
 110         .automatic_shrinking = false,
 111 };
 112
 113 static atomic_t startup_count;
 114 static DECLARE_WAIT_QUEUE_HEAD(startup_wait);
 115
 116 static int insert_retry(struct rhashtable *ht, struct test_obj *obj,
 117                         const struct rhashtable_params params)
 118 {
 119         int err, retries = -1, enomem_retries = 0;
 120
 121         do {
 122                 retries++;
 123                 cond_resched();
 124                 err = rhashtable_insert_fast(ht, &obj->node, params);
 125                 if (err == -ENOMEM && enomem_retry) {
 126                         enomem_retries++;
 127                         err = -EBUSY;
 128                 }
 129         } while (err == -EBUSY);
 130
 131         if (enomem_retries)
 132                 pr_info(" %u insertions retried after -ENOMEM\n",
 133                         enomem_retries);
 134
 135         return err ? : retries;
 136 }
 137
 138 static int __init test_rht_lookup(struct rhashtable *ht, struct test_obj *array,
 139                                   unsigned int entries)
 140 {
 141         unsigned int i;
 142
 143         for (i = 0; i < entries; i++) {
 144                 struct test_obj *obj;
 145                 bool expected = !(i % 2);
 146                 struct test_obj_val key = {
 147                         .id = i,
 148                 };
 149
 150                 if (array[i / 2].value.id == TEST_INSERT_FAIL)
 151                         expected = false;
 152
 153                 obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
 154
 155                 if (expected && !obj) {
 156                         pr_warn("Test failed: Could not find key %u\n", key.id);
 157                         return -ENOENT;
 158                 } else if (!expected && obj) {
 159                         pr_warn("Test failed: Unexpected entry found for key %u\n",
 160                                 key.id);
 161                         return -EEXIST;
 162                 } else if (expected && obj) {
 163                         if (obj->value.id != i) {
 164                                 pr_warn("Test failed: Lookup value mismatch %u!=%u\n",
 165                                         obj->value.id, i);
 166                                 return -EINVAL;
 167                         }
 168                 }
 169
 170                 cond_resched_rcu();
 171         }
 172
 173         return 0;
 174 }
 175
 176 static void test_bucket_stats(struct rhashtable *ht, unsigned int entries)
 177 {
 178         unsigned int total = 0, chain_len = 0;
 179         struct rhashtable_iter hti;
 180         struct rhash_head *pos;
 181
 182         rhashtable_walk_enter(ht, &hti);
 183         rhashtable_walk_start(&hti);
 184
 185         while ((pos = rhashtable_walk_next(&hti))) {
 186                 if (PTR_ERR(pos) == -EAGAIN) {
 187                         pr_info("Info: encountered resize\n");
 188                         chain_len++;
 189                         continue;
 190                 } else if (IS_ERR(pos)) {
 191                         pr_warn("Test failed: rhashtable_walk_next() error: %ld\n",
 192                                 PTR_ERR(pos));
 193                         break;
 194                 }
 195
 196                 total++;
 197         }
 198
 199         rhashtable_walk_stop(&hti);
 200         rhashtable_walk_exit(&hti);
 201
 202         pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d, table-jumps=%u\n",
 203                 total, atomic_read(&ht->nelems), entries, chain_len);
 204
 205         if (total != atomic_read(&ht->nelems) || total != entries)
 206                 pr_warn("Test failed: Total count mismatch ^^^");
 207 }
 208
 209 static s64 __init test_rhashtable(struct rhashtable *ht, struct test_obj *array,
 210                                   unsigned int entries)
 211 {
 212         struct test_obj *obj;
 213         int err;
 214         unsigned int i, insert_retries = 0;
 215         s64 start, end;
 216
 217         /*
 218          * Insertion Test:
 219          * Insert entries into table with all keys even numbers
 220          */
 221         pr_info("  Adding %d keys\n", entries);
 222         start = ktime_get_ns();
 223         for (i = 0; i < entries; i++) {
 224                 struct test_obj *obj = &array[i];
 225
 226                 obj->value.id = i * 2;
 227                 err = insert_retry(ht, obj, test_rht_params);
 228                 if (err > 0)
 229                         insert_retries += err;
 230                 else if (err)
 231                         return err;
 232         }
 233
 234         if (insert_retries)
 235                 pr_info("  %u insertions retried due to memory pressure\n",
 236                         insert_retries);
 237
 238         test_bucket_stats(ht, entries);
 239         rcu_read_lock();
 240         test_rht_lookup(ht, array, entries);
 241         rcu_read_unlock();
 242
 243         test_bucket_stats(ht, entries);
 244
 245         pr_info("  Deleting %d keys\n", entries);
 246         for (i = 0; i < entries; i++) {
 247                 struct test_obj_val key = {
 248                         .id = i * 2,
 249                 };
 250
 251                 if (array[i].value.id != TEST_INSERT_FAIL) {
 252                         obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
 253                         BUG_ON(!obj);
 254
 255                         rhashtable_remove_fast(ht, &obj->node, test_rht_params);
 256                 }
 257
 258                 cond_resched();
 259         }
 260
 261         end = ktime_get_ns();
 262         pr_info("  Duration of test: %lld ns\n", end - start);
 263
 264         return end - start;
 265 }
 266
 267 static struct rhashtable ht;
 268 static struct rhltable rhlt;
 269
 270 static int __init test_rhltable(unsigned int entries)
 271 {
 272         struct test_obj_rhl *rhl_test_objects;
 273         unsigned long *obj_in_table;
 274         unsigned int i, j, k;
 275         int ret, err;
 276
 277         if (entries == 0)
 278                 entries = 1;
 279
 280         rhl_test_objects = vzalloc(array_size(entries,
 281                                               sizeof(*rhl_test_objects)));
 282         if (!rhl_test_objects)
 283                 return -ENOMEM;
 284
 285         ret = -ENOMEM;
 286         obj_in_table = vzalloc(array_size(sizeof(unsigned long),
 287                                           BITS_TO_LONGS(entries)));
 288         if (!obj_in_table)
 289                 goto out_free;
 290
 291         err = rhltable_init(&rhlt, &test_rht_params);
 292         if (WARN_ON(err))
 293                 goto out_free;
 294
 295         k = get_random_u32();
 296         ret = 0;
 297         for (i = 0; i < entries; i++) {
 298                 rhl_test_objects[i].value.id = k;
 299                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
 300                                       test_rht_params);
 301                 if (WARN(err, "error %d on element %d\n", err, i))
 302                         break;
 303                 if (err == 0)
 304                         set_bit(i, obj_in_table);
 305         }
 306
 307         if (err)
 308                 ret = err;
 309
 310         pr_info("test %d add/delete pairs into rhlist\n", entries);
 311         for (i = 0; i < entries; i++) {
 312                 struct rhlist_head *h, *pos;
 313                 struct test_obj_rhl *obj;
 314                 struct test_obj_val key = {
 315                         .id = k,
 316                 };
 317                 bool found;
 318
 319                 rcu_read_lock();
 320                 h = rhltable_lookup(&rhlt, &key, test_rht_params);
 321                 if (WARN(!h, "key not found during iteration %d of %d", i, entries)) {
 322                         rcu_read_unlock();
 323                         break;
 324                 }
 325
 326                 if (i) {
 327                         j = i - 1;
 328                         rhl_for_each_entry_rcu(obj, pos, h, list_node) {
 329                                 if (WARN(pos == &rhl_test_objects[j].list_node, "old element found, should be gone"))
 330                                         break;
 331                         }
 332                 }
 333
 334                 cond_resched_rcu();
 335
 336                 found = false;
 337
 338                 rhl_for_each_entry_rcu(obj, pos, h, list_node) {
 339                         if (pos == &rhl_test_objects[i].list_node) {
 340                                 found = true;
 341                                 break;
 342                         }
 343                 }
 344
 345                 rcu_read_unlock();
 346
 347                 if (WARN(!found, "element %d not found", i))
 348                         break;
 349
 350                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 351                 WARN(err, "rhltable_remove: err %d for iteration %d\n", err, i);
 352                 if (err == 0)
 353                         clear_bit(i, obj_in_table);
 354         }
 355
 356         if (ret == 0 && err)
 357                 ret = err;
 358
 359         for (i = 0; i < entries; i++) {
 360                 WARN(test_bit(i, obj_in_table), "elem %d allegedly still present", i);
 361
 362                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
 363                                       test_rht_params);
 364                 if (WARN(err, "error %d on element %d\n", err, i))
 365                         break;
 366                 if (err == 0)
 367                         set_bit(i, obj_in_table);
 368         }
 369
 370         pr_info("test %d random rhlist add/delete operations\n", entries);
 371         for (j = 0; j < entries; j++) {
 372                 u32 i = get_random_u32_below(entries);
 373                 u32 prand = get_random_u32_below(4);
 374
 375                 cond_resched();
 376
 377                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 378                 if (test_bit(i, obj_in_table)) {
 379                         clear_bit(i, obj_in_table);
 380                         if (WARN(err, "cannot remove element at slot %d", i))
 381                                 continue;
 382                 } else {
 383                         if (WARN(err != -ENOENT, "removed non-existent element %d, error %d not %d",
 384                              i, err, -ENOENT))
 385                                 continue;
 386                 }
 387
 388                 if (prand & 1) {
 389                         err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 390                         if (err == 0) {
 391                                 if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
 392                                         continue;
 393                         } else {
 394                                 if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
 395                                         continue;
 396                         }
 397                 }
 398
 399                 if (prand & 2) {
 400                         i = get_random_u32_below(entries);
 401                         if (test_bit(i, obj_in_table)) {
 402                                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 403                                 WARN(err, "cannot remove element at slot %d", i);
 404                                 if (err == 0)
 405                                         clear_bit(i, obj_in_table);
 406                         } else {
 407                                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 408                                 WARN(err, "failed to insert object %d", i);
 409                                 if (err == 0)
 410                                         set_bit(i, obj_in_table);
 411                         }
 412                 }
 413         }
 414
 415         for (i = 0; i < entries; i++) {
 416                 cond_resched();
 417                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
 418                 if (test_bit(i, obj_in_table)) {
 419                         if (WARN(err, "cannot remove element at slot %d", i))
 420                                 continue;
 421                 } else {
 422                         if (WARN(err != -ENOENT, "removed non-existent element, error %d not %d",
 423                                  err, -ENOENT))
 424                                 continue;
 425                 }
 426         }
 427
 428         rhltable_destroy(&rhlt);
 429 out_free:
 430         vfree(rhl_test_objects);
 431         vfree(obj_in_table);
 432         return ret;
 433 }
 434
 435 static int __init test_rhashtable_max(struct test_obj *array,
 436                                       unsigned int entries)
 437 {
 438         unsigned int i;
 439         int err;
 440
 441         test_rht_params.max_size = roundup_pow_of_two(entries / 8);
 442         err = rhashtable_init(&ht, &test_rht_params);
 443         if (err)
 444                 return err;
 445
 446         for (i = 0; i < ht.max_elems; i++) {
 447                 struct test_obj *obj = &array[i];
 448
 449                 obj->value.id = i * 2;
 450                 err = insert_retry(&ht, obj, test_rht_params);
 451                 if (err < 0)
 452                         return err;
 453         }
 454
 455         err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
 456         if (err == -E2BIG) {
 457                 err = 0;
 458         } else {
 459                 pr_info("insert element %u should have failed with %d, got %d\n",
 460                                 ht.max_elems, -E2BIG, err);
 461                 if (err == 0)
 462                         err = -1;
 463         }
 464
 465         rhashtable_destroy(&ht);
 466
 467         return err;
 468 }
 469
 470 static unsigned int __init print_ht(struct rhltable *rhlt)
 471 {
 472         struct rhashtable *ht;
 473         const struct bucket_table *tbl;
 474         char buff[512] = "";
 475         int offset = 0;
 476         unsigned int i, cnt = 0;
 477
 478         ht = &rhlt->ht;
 479         /* Take the mutex to avoid RCU warning */
 480         mutex_lock(&ht->mutex);
 481         tbl = rht_dereference(ht->tbl, ht);
 482         for (i = 0; i < tbl->size; i++) {
 483                 struct rhash_head *pos, *next;
 484                 struct test_obj_rhl *p;
 485
 486                 pos = rht_ptr_exclusive(tbl->buckets + i);
 487                 next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
 488
 489                 if (!rht_is_a_nulls(pos)) {
 490                         offset += sprintf(buff + offset, "\nbucket[%d] -> ", i);
 491                 }
 492
 493                 while (!rht_is_a_nulls(pos)) {
 494                         struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
 495                         offset += sprintf(buff + offset, "[[");
 496                         do {
 497                                 pos = &list->rhead;
 498                                 list = rht_dereference(list->next, ht);
 499                                 p = rht_obj(ht, pos);
 500
 501                                 offset += sprintf(buff + offset, " val %d (tid=%d)%s", p->value.id, p->value.tid,
 502                                         list? ", " : " ");
 503                                 cnt++;
 504                         } while (list);
 505
 506                         pos = next,
 507                         next = !rht_is_a_nulls(pos) ?
 508                                 rht_dereference(pos->next, ht) : NULL;
 509
 510                         offset += sprintf(buff + offset, "]]%s", !rht_is_a_nulls(pos) ? " -> " : "");
 511                 }
 512         }
 513         printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
 514         mutex_unlock(&ht->mutex);
 515
 516         return cnt;
 517 }
 518
 519 static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
 520                                   int cnt, bool slow)
 521 {
 522         struct rhltable *rhlt;
 523         unsigned int i, ret;
 524         const char *key;
 525         int err = 0;
 526
 527         rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
 528         if (WARN_ON(!rhlt))
 529                 return -EINVAL;
 530
 531         err = rhltable_init(rhlt, &test_rht_params_dup);
 532         if (WARN_ON(err)) {
 533                 kfree(rhlt);
 534                 return err;
 535         }
 536
 537         for (i = 0; i < cnt; i++) {
 538                 rhl_test_objects[i].value.tid = i;
 539                 key = rht_obj(&rhlt->ht, &rhl_test_objects[i].list_node.rhead);
 540                 key += test_rht_params_dup.key_offset;
 541
 542                 if (slow) {
 543                         err = PTR_ERR(rhashtable_insert_slow(&rhlt->ht, key,
 544                                                              &rhl_test_objects[i].list_node.rhead));
 545                         if (err == -EAGAIN)
 546                                 err = 0;
 547                 } else
 548                         err = rhltable_insert(rhlt,
 549                                               &rhl_test_objects[i].list_node,
 550                                               test_rht_params_dup);
 551                 if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
 552                         goto skip_print;
 553         }
 554
 555         ret = print_ht(rhlt);
 556         WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
 557
 558 skip_print:
 559         rhltable_destroy(rhlt);
 560         kfree(rhlt);
 561
 562         return 0;
 563 }
 564
 565 static int __init test_insert_duplicates_run(void)
 566 {
 567         struct test_obj_rhl rhl_test_objects[3] = {};
 568
 569         pr_info("test inserting duplicates\n");
 570
 571         /* two different values that map to same bucket */
 572         rhl_test_objects[0].value.id = 1;
 573         rhl_test_objects[1].value.id = 21;
 574
 575         /* and another duplicate with same as [0] value
 576          * which will be second on the bucket list */
 577         rhl_test_objects[2].value.id = rhl_test_objects[0].value.id;
 578
 579         test_insert_dup(rhl_test_objects, 2, false);
 580         test_insert_dup(rhl_test_objects, 3, false);
 581         test_insert_dup(rhl_test_objects, 2, true);
 582         test_insert_dup(rhl_test_objects, 3, true);
 583
 584         return 0;
 585 }
 586
 587 static int thread_lookup_test(struct thread_data *tdata)
 588 {
 589         unsigned int entries = tdata->entries;
 590         int i, err = 0;
 591
 592         for (i = 0; i < entries; i++) {
 593                 struct test_obj *obj;
 594                 struct test_obj_val key = {
 595                         .id = i,
 596                         .tid = tdata->id,
 597                 };
 598
 599                 obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
 600                 if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
 601                         pr_err("  found unexpected object %d-%d\n", key.tid, key.id);
 602                         err++;
 603                 } else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
 604                         pr_err("  object %d-%d not found!\n", key.tid, key.id);
 605                         err++;
 606                 } else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
 607                         pr_err("  wrong object returned (got %d-%d, expected %d-%d)\n",
 608                                obj->value.tid, obj->value.id, key.tid, key.id);
 609                         err++;
 610                 }
 611
 612                 cond_resched();
 613         }
 614         return err;
 615 }
 616
 617 static int threadfunc(void *data)
 618 {
 619         int i, step, err = 0, insert_retries = 0;
 620         struct thread_data *tdata = data;
 621
 622         if (atomic_dec_and_test(&startup_count))
 623                 wake_up(&startup_wait);
 624         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == -1)) {
 625                 pr_err("  thread[%d]: interrupted\n", tdata->id);
 626                 goto out;
 627         }
 628
 629         for (i = 0; i < tdata->entries; i++) {
 630                 tdata->objs[i].value.id = i;
 631                 tdata->objs[i].value.tid = tdata->id;
 632                 err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
 633                 if (err > 0) {
 634                         insert_retries += err;
 635                 } else if (err) {
 636                         pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
 637                                tdata->id);
 638                         goto out;
 639                 }
 640         }
 641         if (insert_retries)
 642                 pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
 643                         tdata->id, insert_retries);
 644
 645         err = thread_lookup_test(tdata);
 646         if (err) {
 647                 pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
 648                        tdata->id);
 649                 goto out;
 650         }
 651
 652         for (step = 10; step > 0; step--) {
 653                 for (i = 0; i < tdata->entries; i += step) {
 654                         if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
 655                                 continue;
 656                         err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
 657                                                      test_rht_params);
 658                         if (err) {
 659                                 pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
 660                                        tdata->id);
 661                                 goto out;
 662                         }
 663                         tdata->objs[i].value.id = TEST_INSERT_FAIL;
 664
 665                         cond_resched();
 666                 }
 667                 err = thread_lookup_test(tdata);
 668                 if (err) {
 669                         pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
 670                                tdata->id);
 671                         goto out;
 672                 }
 673         }
 674 out:
 675         while (!kthread_should_stop()) {
 676                 set_current_state(TASK_INTERRUPTIBLE);
 677                 schedule();
 678         }
 679         return err;
 680 }
 681
 682 static int __init test_rht_init(void)
 683 {
 684         unsigned int entries;
 685         int i, err, started_threads = 0, failed_threads = 0;
 686         u64 total_time = 0;
 687         struct thread_data *tdata;
 688         struct test_obj *objs;
 689
 690         if (parm_entries < 0)
 691                 parm_entries = 1;
 692
 693         entries = min(parm_entries, MAX_ENTRIES);
 694
 695         test_rht_params.automatic_shrinking = shrinking;
 696         test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
 697         test_rht_params.nelem_hint = size;
 698
 699         objs = vzalloc(array_size(sizeof(struct test_obj),
 700                                   test_rht_params.max_size + 1));
 701         if (!objs)
 702                 return -ENOMEM;
 703
 704         pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
 705                 size, max_size, shrinking);
 706
 707         for (i = 0; i < runs; i++) {
 708                 s64 time;
 709
 710                 pr_info("Test %02d:\n", i);
 711                 memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
 712
 713                 err = rhashtable_init(&ht, &test_rht_params);
 714                 if (err < 0) {
 715                         pr_warn("Test failed: Unable to initialize hashtable: %d\n",
 716                                 err);
 717                         continue;
 718                 }
 719
 720                 time = test_rhashtable(&ht, objs, entries);
 721                 rhashtable_destroy(&ht);
 722                 if (time < 0) {
 723                         vfree(objs);
 724                         pr_warn("Test failed: return code %lld\n", time);
 725                         return -EINVAL;
 726                 }
 727
 728                 total_time += time;
 729         }
 730
 731         pr_info("test if its possible to exceed max_size %d: %s\n",
 732                         test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
 733                         "no, ok" : "YES, failed");
 734         vfree(objs);
 735
 736         do_div(total_time, runs);
 737         pr_info("Average test time: %llu\n", total_time);
 738
 739         test_insert_duplicates_run();
 740
 741         if (!tcount)
 742                 return 0;
 743
 744         pr_info("Testing concurrent rhashtable access from %d threads\n",
 745                 tcount);
 746         atomic_set(&startup_count, tcount);
 747         tdata = vzalloc(array_size(tcount, sizeof(struct thread_data)));
 748         if (!tdata)
 749                 return -ENOMEM;
 750         objs  = vzalloc(array3_size(sizeof(struct test_obj), tcount, entries));
 751         if (!objs) {
 752                 vfree(tdata);
 753                 return -ENOMEM;
 754         }
 755
 756         test_rht_params.max_size = max_size ? :
 757                                    roundup_pow_of_two(tcount * entries);
 758         err = rhashtable_init(&ht, &test_rht_params);
 759         if (err < 0) {
 760                 pr_warn("Test failed: Unable to initialize hashtable: %d\n",
 761                         err);
 762                 vfree(tdata);
 763                 vfree(objs);
 764                 return -EINVAL;
 765         }
 766         for (i = 0; i < tcount; i++) {
 767                 tdata[i].id = i;
 768                 tdata[i].entries = entries;
 769                 tdata[i].objs = objs + i * entries;
 770                 tdata[i].task = kthread_run(threadfunc, &tdata[i],
 771                                             "rhashtable_thrad[%d]", i);
 772                 if (IS_ERR(tdata[i].task)) {
 773                         pr_err(" kthread_run failed for thread %d\n", i);
 774                         atomic_dec(&startup_count);
 775                 } else {
 776                         started_threads++;
 777                 }
 778         }
 779         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == 0))
 780                 pr_err("  wait_event interruptible failed\n");
 781         /* count is 0 now, set it to -1 and wake up all threads together */
 782         atomic_dec(&startup_count);
 783         wake_up_all(&startup_wait);
 784         for (i = 0; i < tcount; i++) {
 785                 if (IS_ERR(tdata[i].task))
 786                         continue;
 787                 if ((err = kthread_stop(tdata[i].task))) {
 788                         pr_warn("Test failed: thread %d returned: %d\n",
 789                                 i, err);
 790                         failed_threads++;
 791                 }
 792         }
 793         rhashtable_destroy(&ht);
 794         vfree(tdata);
 795         vfree(objs);
 796
 797         /*
 798          * rhltable_remove is very expensive, default values can cause test
 799          * to run for 2 minutes or more,  use a smaller number instead.
 800          */
 801         err = test_rhltable(entries / 16);
 802         pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
 803                 started_threads, failed_threads, err);
 804         return 0;
 805 }
 806
 807 static void __exit test_rht_exit(void)
 808 {
 809 }
 810
 811 module_init(test_rht_init);
 812 module_exit(test_rht_exit);
 813
 814 MODULE_LICENSE("GPL v2");