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