docs: driver-api: usb: avoid using ReST :doc:`foo` markup
[linux-2.6-microblaze.git] / 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 = prandom_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 = prandom_u32_max(entries);
372                 u32 prand = prandom_u32();
373
374                 cond_resched();
375
376                 if (prand == 0)
377                         prand = prandom_u32();
378
379                 if (prand & 1) {
380                         prand >>= 1;
381                         continue;
382                 }
383
384                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
385                 if (test_bit(i, obj_in_table)) {
386                         clear_bit(i, obj_in_table);
387                         if (WARN(err, "cannot remove element at slot %d", i))
388                                 continue;
389                 } else {
390                         if (WARN(err != -ENOENT, "removed non-existent element %d, error %d not %d",
391                              i, err, -ENOENT))
392                                 continue;
393                 }
394
395                 if (prand & 1) {
396                         prand >>= 1;
397                         continue;
398                 }
399
400                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
401                 if (err == 0) {
402                         if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
403                                 continue;
404                 } else {
405                         if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
406                                 continue;
407                 }
408
409                 if (prand & 1) {
410                         prand >>= 1;
411                         continue;
412                 }
413
414                 i = prandom_u32_max(entries);
415                 if (test_bit(i, obj_in_table)) {
416                         err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
417                         WARN(err, "cannot remove element at slot %d", i);
418                         if (err == 0)
419                                 clear_bit(i, obj_in_table);
420                 } else {
421                         err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
422                         WARN(err, "failed to insert object %d", i);
423                         if (err == 0)
424                                 set_bit(i, obj_in_table);
425                 }
426         }
427
428         for (i = 0; i < entries; i++) {
429                 cond_resched();
430                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
431                 if (test_bit(i, obj_in_table)) {
432                         if (WARN(err, "cannot remove element at slot %d", i))
433                                 continue;
434                 } else {
435                         if (WARN(err != -ENOENT, "removed non-existent element, error %d not %d",
436                                  err, -ENOENT))
437                                 continue;
438                 }
439         }
440
441         rhltable_destroy(&rhlt);
442 out_free:
443         vfree(rhl_test_objects);
444         vfree(obj_in_table);
445         return ret;
446 }
447
448 static int __init test_rhashtable_max(struct test_obj *array,
449                                       unsigned int entries)
450 {
451         unsigned int i, insert_retries = 0;
452         int err;
453
454         test_rht_params.max_size = roundup_pow_of_two(entries / 8);
455         err = rhashtable_init(&ht, &test_rht_params);
456         if (err)
457                 return err;
458
459         for (i = 0; i < ht.max_elems; i++) {
460                 struct test_obj *obj = &array[i];
461
462                 obj->value.id = i * 2;
463                 err = insert_retry(&ht, obj, test_rht_params);
464                 if (err > 0)
465                         insert_retries += err;
466                 else if (err)
467                         return err;
468         }
469
470         err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
471         if (err == -E2BIG) {
472                 err = 0;
473         } else {
474                 pr_info("insert element %u should have failed with %d, got %d\n",
475                                 ht.max_elems, -E2BIG, err);
476                 if (err == 0)
477                         err = -1;
478         }
479
480         rhashtable_destroy(&ht);
481
482         return err;
483 }
484
485 static unsigned int __init print_ht(struct rhltable *rhlt)
486 {
487         struct rhashtable *ht;
488         const struct bucket_table *tbl;
489         char buff[512] = "";
490         int offset = 0;
491         unsigned int i, cnt = 0;
492
493         ht = &rhlt->ht;
494         /* Take the mutex to avoid RCU warning */
495         mutex_lock(&ht->mutex);
496         tbl = rht_dereference(ht->tbl, ht);
497         for (i = 0; i < tbl->size; i++) {
498                 struct rhash_head *pos, *next;
499                 struct test_obj_rhl *p;
500
501                 pos = rht_ptr_exclusive(tbl->buckets + i);
502                 next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
503
504                 if (!rht_is_a_nulls(pos)) {
505                         offset += sprintf(buff + offset, "\nbucket[%d] -> ", i);
506                 }
507
508                 while (!rht_is_a_nulls(pos)) {
509                         struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
510                         offset += sprintf(buff + offset, "[[");
511                         do {
512                                 pos = &list->rhead;
513                                 list = rht_dereference(list->next, ht);
514                                 p = rht_obj(ht, pos);
515
516                                 offset += sprintf(buff + offset, " val %d (tid=%d)%s", p->value.id, p->value.tid,
517                                         list? ", " : " ");
518                                 cnt++;
519                         } while (list);
520
521                         pos = next,
522                         next = !rht_is_a_nulls(pos) ?
523                                 rht_dereference(pos->next, ht) : NULL;
524
525                         offset += sprintf(buff + offset, "]]%s", !rht_is_a_nulls(pos) ? " -> " : "");
526                 }
527         }
528         printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
529         mutex_unlock(&ht->mutex);
530
531         return cnt;
532 }
533
534 static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
535                                   int cnt, bool slow)
536 {
537         struct rhltable *rhlt;
538         unsigned int i, ret;
539         const char *key;
540         int err = 0;
541
542         rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
543         if (WARN_ON(!rhlt))
544                 return -EINVAL;
545
546         err = rhltable_init(rhlt, &test_rht_params_dup);
547         if (WARN_ON(err)) {
548                 kfree(rhlt);
549                 return err;
550         }
551
552         for (i = 0; i < cnt; i++) {
553                 rhl_test_objects[i].value.tid = i;
554                 key = rht_obj(&rhlt->ht, &rhl_test_objects[i].list_node.rhead);
555                 key += test_rht_params_dup.key_offset;
556
557                 if (slow) {
558                         err = PTR_ERR(rhashtable_insert_slow(&rhlt->ht, key,
559                                                              &rhl_test_objects[i].list_node.rhead));
560                         if (err == -EAGAIN)
561                                 err = 0;
562                 } else
563                         err = rhltable_insert(rhlt,
564                                               &rhl_test_objects[i].list_node,
565                                               test_rht_params_dup);
566                 if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
567                         goto skip_print;
568         }
569
570         ret = print_ht(rhlt);
571         WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
572
573 skip_print:
574         rhltable_destroy(rhlt);
575         kfree(rhlt);
576
577         return 0;
578 }
579
580 static int __init test_insert_duplicates_run(void)
581 {
582         struct test_obj_rhl rhl_test_objects[3] = {};
583
584         pr_info("test inserting duplicates\n");
585
586         /* two different values that map to same bucket */
587         rhl_test_objects[0].value.id = 1;
588         rhl_test_objects[1].value.id = 21;
589
590         /* and another duplicate with same as [0] value
591          * which will be second on the bucket list */
592         rhl_test_objects[2].value.id = rhl_test_objects[0].value.id;
593
594         test_insert_dup(rhl_test_objects, 2, false);
595         test_insert_dup(rhl_test_objects, 3, false);
596         test_insert_dup(rhl_test_objects, 2, true);
597         test_insert_dup(rhl_test_objects, 3, true);
598
599         return 0;
600 }
601
602 static int thread_lookup_test(struct thread_data *tdata)
603 {
604         unsigned int entries = tdata->entries;
605         int i, err = 0;
606
607         for (i = 0; i < entries; i++) {
608                 struct test_obj *obj;
609                 struct test_obj_val key = {
610                         .id = i,
611                         .tid = tdata->id,
612                 };
613
614                 obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
615                 if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
616                         pr_err("  found unexpected object %d-%d\n", key.tid, key.id);
617                         err++;
618                 } else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
619                         pr_err("  object %d-%d not found!\n", key.tid, key.id);
620                         err++;
621                 } else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
622                         pr_err("  wrong object returned (got %d-%d, expected %d-%d)\n",
623                                obj->value.tid, obj->value.id, key.tid, key.id);
624                         err++;
625                 }
626
627                 cond_resched();
628         }
629         return err;
630 }
631
632 static int threadfunc(void *data)
633 {
634         int i, step, err = 0, insert_retries = 0;
635         struct thread_data *tdata = data;
636
637         if (atomic_dec_and_test(&startup_count))
638                 wake_up(&startup_wait);
639         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == -1)) {
640                 pr_err("  thread[%d]: interrupted\n", tdata->id);
641                 goto out;
642         }
643
644         for (i = 0; i < tdata->entries; i++) {
645                 tdata->objs[i].value.id = i;
646                 tdata->objs[i].value.tid = tdata->id;
647                 err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
648                 if (err > 0) {
649                         insert_retries += err;
650                 } else if (err) {
651                         pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
652                                tdata->id);
653                         goto out;
654                 }
655         }
656         if (insert_retries)
657                 pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
658                         tdata->id, insert_retries);
659
660         err = thread_lookup_test(tdata);
661         if (err) {
662                 pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
663                        tdata->id);
664                 goto out;
665         }
666
667         for (step = 10; step > 0; step--) {
668                 for (i = 0; i < tdata->entries; i += step) {
669                         if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
670                                 continue;
671                         err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
672                                                      test_rht_params);
673                         if (err) {
674                                 pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
675                                        tdata->id);
676                                 goto out;
677                         }
678                         tdata->objs[i].value.id = TEST_INSERT_FAIL;
679
680                         cond_resched();
681                 }
682                 err = thread_lookup_test(tdata);
683                 if (err) {
684                         pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
685                                tdata->id);
686                         goto out;
687                 }
688         }
689 out:
690         while (!kthread_should_stop()) {
691                 set_current_state(TASK_INTERRUPTIBLE);
692                 schedule();
693         }
694         return err;
695 }
696
697 static int __init test_rht_init(void)
698 {
699         unsigned int entries;
700         int i, err, started_threads = 0, failed_threads = 0;
701         u64 total_time = 0;
702         struct thread_data *tdata;
703         struct test_obj *objs;
704
705         if (parm_entries < 0)
706                 parm_entries = 1;
707
708         entries = min(parm_entries, MAX_ENTRIES);
709
710         test_rht_params.automatic_shrinking = shrinking;
711         test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
712         test_rht_params.nelem_hint = size;
713
714         objs = vzalloc(array_size(sizeof(struct test_obj),
715                                   test_rht_params.max_size + 1));
716         if (!objs)
717                 return -ENOMEM;
718
719         pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
720                 size, max_size, shrinking);
721
722         for (i = 0; i < runs; i++) {
723                 s64 time;
724
725                 pr_info("Test %02d:\n", i);
726                 memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
727
728                 err = rhashtable_init(&ht, &test_rht_params);
729                 if (err < 0) {
730                         pr_warn("Test failed: Unable to initialize hashtable: %d\n",
731                                 err);
732                         continue;
733                 }
734
735                 time = test_rhashtable(&ht, objs, entries);
736                 rhashtable_destroy(&ht);
737                 if (time < 0) {
738                         vfree(objs);
739                         pr_warn("Test failed: return code %lld\n", time);
740                         return -EINVAL;
741                 }
742
743                 total_time += time;
744         }
745
746         pr_info("test if its possible to exceed max_size %d: %s\n",
747                         test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
748                         "no, ok" : "YES, failed");
749         vfree(objs);
750
751         do_div(total_time, runs);
752         pr_info("Average test time: %llu\n", total_time);
753
754         test_insert_duplicates_run();
755
756         if (!tcount)
757                 return 0;
758
759         pr_info("Testing concurrent rhashtable access from %d threads\n",
760                 tcount);
761         atomic_set(&startup_count, tcount);
762         tdata = vzalloc(array_size(tcount, sizeof(struct thread_data)));
763         if (!tdata)
764                 return -ENOMEM;
765         objs  = vzalloc(array3_size(sizeof(struct test_obj), tcount, entries));
766         if (!objs) {
767                 vfree(tdata);
768                 return -ENOMEM;
769         }
770
771         test_rht_params.max_size = max_size ? :
772                                    roundup_pow_of_two(tcount * entries);
773         err = rhashtable_init(&ht, &test_rht_params);
774         if (err < 0) {
775                 pr_warn("Test failed: Unable to initialize hashtable: %d\n",
776                         err);
777                 vfree(tdata);
778                 vfree(objs);
779                 return -EINVAL;
780         }
781         for (i = 0; i < tcount; i++) {
782                 tdata[i].id = i;
783                 tdata[i].entries = entries;
784                 tdata[i].objs = objs + i * entries;
785                 tdata[i].task = kthread_run(threadfunc, &tdata[i],
786                                             "rhashtable_thrad[%d]", i);
787                 if (IS_ERR(tdata[i].task)) {
788                         pr_err(" kthread_run failed for thread %d\n", i);
789                         atomic_dec(&startup_count);
790                 } else {
791                         started_threads++;
792                 }
793         }
794         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == 0))
795                 pr_err("  wait_event interruptible failed\n");
796         /* count is 0 now, set it to -1 and wake up all threads together */
797         atomic_dec(&startup_count);
798         wake_up_all(&startup_wait);
799         for (i = 0; i < tcount; i++) {
800                 if (IS_ERR(tdata[i].task))
801                         continue;
802                 if ((err = kthread_stop(tdata[i].task))) {
803                         pr_warn("Test failed: thread %d returned: %d\n",
804                                 i, err);
805                         failed_threads++;
806                 }
807         }
808         rhashtable_destroy(&ht);
809         vfree(tdata);
810         vfree(objs);
811
812         /*
813          * rhltable_remove is very expensive, default values can cause test
814          * to run for 2 minutes or more,  use a smaller number instead.
815          */
816         err = test_rhltable(entries / 16);
817         pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
818                 started_threads, failed_threads, err);
819         return 0;
820 }
821
822 static void __exit test_rht_exit(void)
823 {
824 }
825
826 module_init(test_rht_init);
827 module_exit(test_rht_exit);
828
829 MODULE_LICENSE("GPL v2");