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