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[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         unsigned int i, cnt = 0;
491
492         ht = &rhlt->ht;
493         /* Take the mutex to avoid RCU warning */
494         mutex_lock(&ht->mutex);
495         tbl = rht_dereference(ht->tbl, ht);
496         for (i = 0; i < tbl->size; i++) {
497                 struct rhash_head *pos, *next;
498                 struct test_obj_rhl *p;
499
500                 pos = rht_ptr_exclusive(tbl->buckets + i);
501                 next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
502
503                 if (!rht_is_a_nulls(pos)) {
504                         sprintf(buff, "%s\nbucket[%d] -> ", buff, i);
505                 }
506
507                 while (!rht_is_a_nulls(pos)) {
508                         struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
509                         sprintf(buff, "%s[[", buff);
510                         do {
511                                 pos = &list->rhead;
512                                 list = rht_dereference(list->next, ht);
513                                 p = rht_obj(ht, pos);
514
515                                 sprintf(buff, "%s val %d (tid=%d)%s", buff, p->value.id, p->value.tid,
516                                         list? ", " : " ");
517                                 cnt++;
518                         } while (list);
519
520                         pos = next,
521                         next = !rht_is_a_nulls(pos) ?
522                                 rht_dereference(pos->next, ht) : NULL;
523
524                         sprintf(buff, "%s]]%s", buff, !rht_is_a_nulls(pos) ? " -> " : "");
525                 }
526         }
527         printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
528         mutex_unlock(&ht->mutex);
529
530         return cnt;
531 }
532
533 static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
534                                   int cnt, bool slow)
535 {
536         struct rhltable *rhlt;
537         unsigned int i, ret;
538         const char *key;
539         int err = 0;
540
541         rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
542         if (WARN_ON(!rhlt))
543                 return -EINVAL;
544
545         err = rhltable_init(rhlt, &test_rht_params_dup);
546         if (WARN_ON(err)) {
547                 kfree(rhlt);
548                 return err;
549         }
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
572 skip_print:
573         rhltable_destroy(rhlt);
574         kfree(rhlt);
575
576         return 0;
577 }
578
579 static int __init test_insert_duplicates_run(void)
580 {
581         struct test_obj_rhl rhl_test_objects[3] = {};
582
583         pr_info("test inserting duplicates\n");
584
585         /* two different values that map to same bucket */
586         rhl_test_objects[0].value.id = 1;
587         rhl_test_objects[1].value.id = 21;
588
589         /* and another duplicate with same as [0] value
590          * which will be second on the bucket list */
591         rhl_test_objects[2].value.id = rhl_test_objects[0].value.id;
592
593         test_insert_dup(rhl_test_objects, 2, false);
594         test_insert_dup(rhl_test_objects, 3, false);
595         test_insert_dup(rhl_test_objects, 2, true);
596         test_insert_dup(rhl_test_objects, 3, true);
597
598         return 0;
599 }
600
601 static int thread_lookup_test(struct thread_data *tdata)
602 {
603         unsigned int entries = tdata->entries;
604         int i, err = 0;
605
606         for (i = 0; i < entries; i++) {
607                 struct test_obj *obj;
608                 struct test_obj_val key = {
609                         .id = i,
610                         .tid = tdata->id,
611                 };
612
613                 obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
614                 if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
615                         pr_err("  found unexpected object %d-%d\n", key.tid, key.id);
616                         err++;
617                 } else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
618                         pr_err("  object %d-%d not found!\n", key.tid, key.id);
619                         err++;
620                 } else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
621                         pr_err("  wrong object returned (got %d-%d, expected %d-%d)\n",
622                                obj->value.tid, obj->value.id, key.tid, key.id);
623                         err++;
624                 }
625
626                 cond_resched();
627         }
628         return err;
629 }
630
631 static int threadfunc(void *data)
632 {
633         int i, step, err = 0, insert_retries = 0;
634         struct thread_data *tdata = data;
635
636         if (atomic_dec_and_test(&startup_count))
637                 wake_up(&startup_wait);
638         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == -1)) {
639                 pr_err("  thread[%d]: interrupted\n", tdata->id);
640                 goto out;
641         }
642
643         for (i = 0; i < tdata->entries; i++) {
644                 tdata->objs[i].value.id = i;
645                 tdata->objs[i].value.tid = tdata->id;
646                 err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
647                 if (err > 0) {
648                         insert_retries += err;
649                 } else if (err) {
650                         pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
651                                tdata->id);
652                         goto out;
653                 }
654         }
655         if (insert_retries)
656                 pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
657                         tdata->id, insert_retries);
658
659         err = thread_lookup_test(tdata);
660         if (err) {
661                 pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
662                        tdata->id);
663                 goto out;
664         }
665
666         for (step = 10; step > 0; step--) {
667                 for (i = 0; i < tdata->entries; i += step) {
668                         if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
669                                 continue;
670                         err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
671                                                      test_rht_params);
672                         if (err) {
673                                 pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
674                                        tdata->id);
675                                 goto out;
676                         }
677                         tdata->objs[i].value.id = TEST_INSERT_FAIL;
678
679                         cond_resched();
680                 }
681                 err = thread_lookup_test(tdata);
682                 if (err) {
683                         pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
684                                tdata->id);
685                         goto out;
686                 }
687         }
688 out:
689         while (!kthread_should_stop()) {
690                 set_current_state(TASK_INTERRUPTIBLE);
691                 schedule();
692         }
693         return err;
694 }
695
696 static int __init test_rht_init(void)
697 {
698         unsigned int entries;
699         int i, err, started_threads = 0, failed_threads = 0;
700         u64 total_time = 0;
701         struct thread_data *tdata;
702         struct test_obj *objs;
703
704         if (parm_entries < 0)
705                 parm_entries = 1;
706
707         entries = min(parm_entries, MAX_ENTRIES);
708
709         test_rht_params.automatic_shrinking = shrinking;
710         test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
711         test_rht_params.nelem_hint = size;
712
713         objs = vzalloc(array_size(sizeof(struct test_obj),
714                                   test_rht_params.max_size + 1));
715         if (!objs)
716                 return -ENOMEM;
717
718         pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
719                 size, max_size, shrinking);
720
721         for (i = 0; i < runs; i++) {
722                 s64 time;
723
724                 pr_info("Test %02d:\n", i);
725                 memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
726
727                 err = rhashtable_init(&ht, &test_rht_params);
728                 if (err < 0) {
729                         pr_warn("Test failed: Unable to initialize hashtable: %d\n",
730                                 err);
731                         continue;
732                 }
733
734                 time = test_rhashtable(&ht, objs, entries);
735                 rhashtable_destroy(&ht);
736                 if (time < 0) {
737                         vfree(objs);
738                         pr_warn("Test failed: return code %lld\n", time);
739                         return -EINVAL;
740                 }
741
742                 total_time += time;
743         }
744
745         pr_info("test if its possible to exceed max_size %d: %s\n",
746                         test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
747                         "no, ok" : "YES, failed");
748         vfree(objs);
749
750         do_div(total_time, runs);
751         pr_info("Average test time: %llu\n", total_time);
752
753         test_insert_duplicates_run();
754
755         if (!tcount)
756                 return 0;
757
758         pr_info("Testing concurrent rhashtable access from %d threads\n",
759                 tcount);
760         atomic_set(&startup_count, tcount);
761         tdata = vzalloc(array_size(tcount, sizeof(struct thread_data)));
762         if (!tdata)
763                 return -ENOMEM;
764         objs  = vzalloc(array3_size(sizeof(struct test_obj), tcount, entries));
765         if (!objs) {
766                 vfree(tdata);
767                 return -ENOMEM;
768         }
769
770         test_rht_params.max_size = max_size ? :
771                                    roundup_pow_of_two(tcount * entries);
772         err = rhashtable_init(&ht, &test_rht_params);
773         if (err < 0) {
774                 pr_warn("Test failed: Unable to initialize hashtable: %d\n",
775                         err);
776                 vfree(tdata);
777                 vfree(objs);
778                 return -EINVAL;
779         }
780         for (i = 0; i < tcount; i++) {
781                 tdata[i].id = i;
782                 tdata[i].entries = entries;
783                 tdata[i].objs = objs + i * entries;
784                 tdata[i].task = kthread_run(threadfunc, &tdata[i],
785                                             "rhashtable_thrad[%d]", i);
786                 if (IS_ERR(tdata[i].task)) {
787                         pr_err(" kthread_run failed for thread %d\n", i);
788                         atomic_dec(&startup_count);
789                 } else {
790                         started_threads++;
791                 }
792         }
793         if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == 0))
794                 pr_err("  wait_event interruptible failed\n");
795         /* count is 0 now, set it to -1 and wake up all threads together */
796         atomic_dec(&startup_count);
797         wake_up_all(&startup_wait);
798         for (i = 0; i < tcount; i++) {
799                 if (IS_ERR(tdata[i].task))
800                         continue;
801                 if ((err = kthread_stop(tdata[i].task))) {
802                         pr_warn("Test failed: thread %d returned: %d\n",
803                                 i, err);
804                         failed_threads++;
805                 }
806         }
807         rhashtable_destroy(&ht);
808         vfree(tdata);
809         vfree(objs);
810
811         /*
812          * rhltable_remove is very expensive, default values can cause test
813          * to run for 2 minutes or more,  use a smaller number instead.
814          */
815         err = test_rhltable(entries / 16);
816         pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
817                 started_threads, failed_threads, err);
818         return 0;
819 }
820
821 static void __exit test_rht_exit(void)
822 {
823 }
824
825 module_init(test_rht_init);
826 module_exit(test_rht_exit);
827
828 MODULE_LICENSE("GPL v2");