ipv6 sit: work around bogus gcc-8 -Wrestrict warning
[linux-2.6-microblaze.git] / lib / test_rhashtable.c
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
32 static int parm_entries = 50000;
33 module_param(parm_entries, int, 0);
34 MODULE_PARM_DESC(parm_entries, "Number of entries to add (default: 50000)");
35
36 static int runs = 4;
37 module_param(runs, int, 0);
38 MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)");
39
40 static int max_size = 0;
41 module_param(max_size, int, 0);
42 MODULE_PARM_DESC(max_size, "Maximum table size (default: calculated)");
43
44 static bool shrinking = false;
45 module_param(shrinking, bool, 0);
46 MODULE_PARM_DESC(shrinking, "Enable automatic shrinking (default: off)");
47
48 static int size = 8;
49 module_param(size, int, 0);
50 MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)");
51
52 static int tcount = 10;
53 module_param(tcount, int, 0);
54 MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");
55
56 static bool enomem_retry = false;
57 module_param(enomem_retry, bool, 0);
58 MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");
59
60 struct test_obj_val {
61         int     id;
62         int     tid;
63 };
64
65 struct test_obj {
66         struct test_obj_val     value;
67         struct rhash_head       node;
68 };
69
70 struct test_obj_rhl {
71         struct test_obj_val     value;
72         struct rhlist_head      list_node;
73 };
74
75 struct thread_data {
76         unsigned int entries;
77         int id;
78         struct task_struct *task;
79         struct test_obj *objs;
80 };
81
82 static struct rhashtable_params test_rht_params = {
83         .head_offset = offsetof(struct test_obj, node),
84         .key_offset = offsetof(struct test_obj, value),
85         .key_len = sizeof(struct test_obj_val),
86         .hashfn = jhash,
87         .nulls_base = (3U << RHT_BASE_SHIFT),
88 };
89
90 static struct semaphore prestart_sem;
91 static struct semaphore startup_sem = __SEMAPHORE_INITIALIZER(startup_sem, 0);
92
93 static int insert_retry(struct rhashtable *ht, struct test_obj *obj,
94                         const struct rhashtable_params params)
95 {
96         int err, retries = -1, enomem_retries = 0;
97
98         do {
99                 retries++;
100                 cond_resched();
101                 err = rhashtable_insert_fast(ht, &obj->node, params);
102                 if (err == -ENOMEM && enomem_retry) {
103                         enomem_retries++;
104                         err = -EBUSY;
105                 }
106         } while (err == -EBUSY);
107
108         if (enomem_retries)
109                 pr_info(" %u insertions retried after -ENOMEM\n",
110                         enomem_retries);
111
112         return err ? : retries;
113 }
114
115 static int __init test_rht_lookup(struct rhashtable *ht, struct test_obj *array,
116                                   unsigned int entries)
117 {
118         unsigned int i;
119
120         for (i = 0; i < entries; i++) {
121                 struct test_obj *obj;
122                 bool expected = !(i % 2);
123                 struct test_obj_val key = {
124                         .id = i,
125                 };
126
127                 if (array[i / 2].value.id == TEST_INSERT_FAIL)
128                         expected = false;
129
130                 obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
131
132                 if (expected && !obj) {
133                         pr_warn("Test failed: Could not find key %u\n", key.id);
134                         return -ENOENT;
135                 } else if (!expected && obj) {
136                         pr_warn("Test failed: Unexpected entry found for key %u\n",
137                                 key.id);
138                         return -EEXIST;
139                 } else if (expected && obj) {
140                         if (obj->value.id != i) {
141                                 pr_warn("Test failed: Lookup value mismatch %u!=%u\n",
142                                         obj->value.id, i);
143                                 return -EINVAL;
144                         }
145                 }
146
147                 cond_resched_rcu();
148         }
149
150         return 0;
151 }
152
153 static void test_bucket_stats(struct rhashtable *ht, unsigned int entries)
154 {
155         unsigned int err, total = 0, chain_len = 0;
156         struct rhashtable_iter hti;
157         struct rhash_head *pos;
158
159         err = rhashtable_walk_init(ht, &hti, GFP_KERNEL);
160         if (err) {
161                 pr_warn("Test failed: allocation error");
162                 return;
163         }
164
165         rhashtable_walk_start(&hti);
166
167         while ((pos = rhashtable_walk_next(&hti))) {
168                 if (PTR_ERR(pos) == -EAGAIN) {
169                         pr_info("Info: encountered resize\n");
170                         chain_len++;
171                         continue;
172                 } else if (IS_ERR(pos)) {
173                         pr_warn("Test failed: rhashtable_walk_next() error: %ld\n",
174                                 PTR_ERR(pos));
175                         break;
176                 }
177
178                 total++;
179         }
180
181         rhashtable_walk_stop(&hti);
182         rhashtable_walk_exit(&hti);
183
184         pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d, table-jumps=%u\n",
185                 total, atomic_read(&ht->nelems), entries, chain_len);
186
187         if (total != atomic_read(&ht->nelems) || total != entries)
188                 pr_warn("Test failed: Total count mismatch ^^^");
189 }
190
191 static s64 __init test_rhashtable(struct rhashtable *ht, struct test_obj *array,
192                                   unsigned int entries)
193 {
194         struct test_obj *obj;
195         int err;
196         unsigned int i, insert_retries = 0;
197         s64 start, end;
198
199         /*
200          * Insertion Test:
201          * Insert entries into table with all keys even numbers
202          */
203         pr_info("  Adding %d keys\n", entries);
204         start = ktime_get_ns();
205         for (i = 0; i < entries; i++) {
206                 struct test_obj *obj = &array[i];
207
208                 obj->value.id = i * 2;
209                 err = insert_retry(ht, obj, test_rht_params);
210                 if (err > 0)
211                         insert_retries += err;
212                 else if (err)
213                         return err;
214         }
215
216         if (insert_retries)
217                 pr_info("  %u insertions retried due to memory pressure\n",
218                         insert_retries);
219
220         test_bucket_stats(ht, entries);
221         rcu_read_lock();
222         test_rht_lookup(ht, array, entries);
223         rcu_read_unlock();
224
225         test_bucket_stats(ht, entries);
226
227         pr_info("  Deleting %d keys\n", entries);
228         for (i = 0; i < entries; i++) {
229                 struct test_obj_val key = {
230                         .id = i * 2,
231                 };
232
233                 if (array[i].value.id != TEST_INSERT_FAIL) {
234                         obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
235                         BUG_ON(!obj);
236
237                         rhashtable_remove_fast(ht, &obj->node, test_rht_params);
238                 }
239
240                 cond_resched();
241         }
242
243         end = ktime_get_ns();
244         pr_info("  Duration of test: %lld ns\n", end - start);
245
246         return end - start;
247 }
248
249 static struct rhashtable ht;
250 static struct rhltable rhlt;
251
252 static int __init test_rhltable(unsigned int entries)
253 {
254         struct test_obj_rhl *rhl_test_objects;
255         unsigned long *obj_in_table;
256         unsigned int i, j, k;
257         int ret, err;
258
259         if (entries == 0)
260                 entries = 1;
261
262         rhl_test_objects = vzalloc(sizeof(*rhl_test_objects) * entries);
263         if (!rhl_test_objects)
264                 return -ENOMEM;
265
266         ret = -ENOMEM;
267         obj_in_table = vzalloc(BITS_TO_LONGS(entries) * sizeof(unsigned long));
268         if (!obj_in_table)
269                 goto out_free;
270
271         /* nulls_base not supported in rhlist interface */
272         test_rht_params.nulls_base = 0;
273         err = rhltable_init(&rhlt, &test_rht_params);
274         if (WARN_ON(err))
275                 goto out_free;
276
277         k = prandom_u32();
278         ret = 0;
279         for (i = 0; i < entries; i++) {
280                 rhl_test_objects[i].value.id = k;
281                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
282                                       test_rht_params);
283                 if (WARN(err, "error %d on element %d\n", err, i))
284                         break;
285                 if (err == 0)
286                         set_bit(i, obj_in_table);
287         }
288
289         if (err)
290                 ret = err;
291
292         pr_info("test %d add/delete pairs into rhlist\n", entries);
293         for (i = 0; i < entries; i++) {
294                 struct rhlist_head *h, *pos;
295                 struct test_obj_rhl *obj;
296                 struct test_obj_val key = {
297                         .id = k,
298                 };
299                 bool found;
300
301                 rcu_read_lock();
302                 h = rhltable_lookup(&rhlt, &key, test_rht_params);
303                 if (WARN(!h, "key not found during iteration %d of %d", i, entries)) {
304                         rcu_read_unlock();
305                         break;
306                 }
307
308                 if (i) {
309                         j = i - 1;
310                         rhl_for_each_entry_rcu(obj, pos, h, list_node) {
311                                 if (WARN(pos == &rhl_test_objects[j].list_node, "old element found, should be gone"))
312                                         break;
313                         }
314                 }
315
316                 cond_resched_rcu();
317
318                 found = false;
319
320                 rhl_for_each_entry_rcu(obj, pos, h, list_node) {
321                         if (pos == &rhl_test_objects[i].list_node) {
322                                 found = true;
323                                 break;
324                         }
325                 }
326
327                 rcu_read_unlock();
328
329                 if (WARN(!found, "element %d not found", i))
330                         break;
331
332                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
333                 WARN(err, "rhltable_remove: err %d for iteration %d\n", err, i);
334                 if (err == 0)
335                         clear_bit(i, obj_in_table);
336         }
337
338         if (ret == 0 && err)
339                 ret = err;
340
341         for (i = 0; i < entries; i++) {
342                 WARN(test_bit(i, obj_in_table), "elem %d allegedly still present", i);
343
344                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
345                                       test_rht_params);
346                 if (WARN(err, "error %d on element %d\n", err, i))
347                         break;
348                 if (err == 0)
349                         set_bit(i, obj_in_table);
350         }
351
352         pr_info("test %d random rhlist add/delete operations\n", entries);
353         for (j = 0; j < entries; j++) {
354                 u32 i = prandom_u32_max(entries);
355                 u32 prand = prandom_u32();
356
357                 cond_resched();
358
359                 if (prand == 0)
360                         prand = prandom_u32();
361
362                 if (prand & 1) {
363                         prand >>= 1;
364                         continue;
365                 }
366
367                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
368                 if (test_bit(i, obj_in_table)) {
369                         clear_bit(i, obj_in_table);
370                         if (WARN(err, "cannot remove element at slot %d", i))
371                                 continue;
372                 } else {
373                         if (WARN(err != -ENOENT, "removed non-existant element %d, error %d not %d",
374                              i, err, -ENOENT))
375                                 continue;
376                 }
377
378                 if (prand & 1) {
379                         prand >>= 1;
380                         continue;
381                 }
382
383                 err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
384                 if (err == 0) {
385                         if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
386                                 continue;
387                 } else {
388                         if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
389                                 continue;
390                 }
391
392                 if (prand & 1) {
393                         prand >>= 1;
394                         continue;
395                 }
396
397                 i = prandom_u32_max(entries);
398                 if (test_bit(i, obj_in_table)) {
399                         err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
400                         WARN(err, "cannot remove element at slot %d", i);
401                         if (err == 0)
402                                 clear_bit(i, obj_in_table);
403                 } else {
404                         err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
405                         WARN(err, "failed to insert object %d", i);
406                         if (err == 0)
407                                 set_bit(i, obj_in_table);
408                 }
409         }
410
411         for (i = 0; i < entries; i++) {
412                 cond_resched();
413                 err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
414                 if (test_bit(i, obj_in_table)) {
415                         if (WARN(err, "cannot remove element at slot %d", i))
416                                 continue;
417                 } else {
418                         if (WARN(err != -ENOENT, "removed non-existant element, error %d not %d",
419                                  err, -ENOENT))
420                         continue;
421                 }
422         }
423
424         rhltable_destroy(&rhlt);
425 out_free:
426         vfree(rhl_test_objects);
427         vfree(obj_in_table);
428         return ret;
429 }
430
431 static int __init test_rhashtable_max(struct test_obj *array,
432                                       unsigned int entries)
433 {
434         unsigned int i, insert_retries = 0;
435         int err;
436
437         test_rht_params.max_size = roundup_pow_of_two(entries / 8);
438         err = rhashtable_init(&ht, &test_rht_params);
439         if (err)
440                 return err;
441
442         for (i = 0; i < ht.max_elems; i++) {
443                 struct test_obj *obj = &array[i];
444
445                 obj->value.id = i * 2;
446                 err = insert_retry(&ht, obj, test_rht_params);
447                 if (err > 0)
448                         insert_retries += err;
449                 else if (err)
450                         return err;
451         }
452
453         err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
454         if (err == -E2BIG) {
455                 err = 0;
456         } else {
457                 pr_info("insert element %u should have failed with %d, got %d\n",
458                                 ht.max_elems, -E2BIG, err);
459                 if (err == 0)
460                         err = -1;
461         }
462
463         rhashtable_destroy(&ht);
464
465         return err;
466 }
467
468 static int thread_lookup_test(struct thread_data *tdata)
469 {
470         unsigned int entries = tdata->entries;
471         int i, err = 0;
472
473         for (i = 0; i < entries; i++) {
474                 struct test_obj *obj;
475                 struct test_obj_val key = {
476                         .id = i,
477                         .tid = tdata->id,
478                 };
479
480                 obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
481                 if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
482                         pr_err("  found unexpected object %d-%d\n", key.tid, key.id);
483                         err++;
484                 } else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
485                         pr_err("  object %d-%d not found!\n", key.tid, key.id);
486                         err++;
487                 } else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
488                         pr_err("  wrong object returned (got %d-%d, expected %d-%d)\n",
489                                obj->value.tid, obj->value.id, key.tid, key.id);
490                         err++;
491                 }
492
493                 cond_resched();
494         }
495         return err;
496 }
497
498 static int threadfunc(void *data)
499 {
500         int i, step, err = 0, insert_retries = 0;
501         struct thread_data *tdata = data;
502
503         up(&prestart_sem);
504         if (down_interruptible(&startup_sem))
505                 pr_err("  thread[%d]: down_interruptible failed\n", tdata->id);
506
507         for (i = 0; i < tdata->entries; i++) {
508                 tdata->objs[i].value.id = i;
509                 tdata->objs[i].value.tid = tdata->id;
510                 err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
511                 if (err > 0) {
512                         insert_retries += err;
513                 } else if (err) {
514                         pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
515                                tdata->id);
516                         goto out;
517                 }
518         }
519         if (insert_retries)
520                 pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
521                         tdata->id, insert_retries);
522
523         err = thread_lookup_test(tdata);
524         if (err) {
525                 pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
526                        tdata->id);
527                 goto out;
528         }
529
530         for (step = 10; step > 0; step--) {
531                 for (i = 0; i < tdata->entries; i += step) {
532                         if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
533                                 continue;
534                         err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
535                                                      test_rht_params);
536                         if (err) {
537                                 pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
538                                        tdata->id);
539                                 goto out;
540                         }
541                         tdata->objs[i].value.id = TEST_INSERT_FAIL;
542
543                         cond_resched();
544                 }
545                 err = thread_lookup_test(tdata);
546                 if (err) {
547                         pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
548                                tdata->id);
549                         goto out;
550                 }
551         }
552 out:
553         while (!kthread_should_stop()) {
554                 set_current_state(TASK_INTERRUPTIBLE);
555                 schedule();
556         }
557         return err;
558 }
559
560 static int __init test_rht_init(void)
561 {
562         unsigned int entries;
563         int i, err, started_threads = 0, failed_threads = 0;
564         u64 total_time = 0;
565         struct thread_data *tdata;
566         struct test_obj *objs;
567
568         if (parm_entries < 0)
569                 parm_entries = 1;
570
571         entries = min(parm_entries, MAX_ENTRIES);
572
573         test_rht_params.automatic_shrinking = shrinking;
574         test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
575         test_rht_params.nelem_hint = size;
576
577         objs = vzalloc((test_rht_params.max_size + 1) * sizeof(struct test_obj));
578         if (!objs)
579                 return -ENOMEM;
580
581         pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
582                 size, max_size, shrinking);
583
584         for (i = 0; i < runs; i++) {
585                 s64 time;
586
587                 pr_info("Test %02d:\n", i);
588                 memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
589
590                 err = rhashtable_init(&ht, &test_rht_params);
591                 if (err < 0) {
592                         pr_warn("Test failed: Unable to initialize hashtable: %d\n",
593                                 err);
594                         continue;
595                 }
596
597                 time = test_rhashtable(&ht, objs, entries);
598                 rhashtable_destroy(&ht);
599                 if (time < 0) {
600                         vfree(objs);
601                         pr_warn("Test failed: return code %lld\n", time);
602                         return -EINVAL;
603                 }
604
605                 total_time += time;
606         }
607
608         pr_info("test if its possible to exceed max_size %d: %s\n",
609                         test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
610                         "no, ok" : "YES, failed");
611         vfree(objs);
612
613         do_div(total_time, runs);
614         pr_info("Average test time: %llu\n", total_time);
615
616         if (!tcount)
617                 return 0;
618
619         pr_info("Testing concurrent rhashtable access from %d threads\n",
620                 tcount);
621         sema_init(&prestart_sem, 1 - tcount);
622         tdata = vzalloc(tcount * sizeof(struct thread_data));
623         if (!tdata)
624                 return -ENOMEM;
625         objs  = vzalloc(tcount * entries * sizeof(struct test_obj));
626         if (!objs) {
627                 vfree(tdata);
628                 return -ENOMEM;
629         }
630
631         test_rht_params.max_size = max_size ? :
632                                    roundup_pow_of_two(tcount * entries);
633         err = rhashtable_init(&ht, &test_rht_params);
634         if (err < 0) {
635                 pr_warn("Test failed: Unable to initialize hashtable: %d\n",
636                         err);
637                 vfree(tdata);
638                 vfree(objs);
639                 return -EINVAL;
640         }
641         for (i = 0; i < tcount; i++) {
642                 tdata[i].id = i;
643                 tdata[i].entries = entries;
644                 tdata[i].objs = objs + i * entries;
645                 tdata[i].task = kthread_run(threadfunc, &tdata[i],
646                                             "rhashtable_thrad[%d]", i);
647                 if (IS_ERR(tdata[i].task))
648                         pr_err(" kthread_run failed for thread %d\n", i);
649                 else
650                         started_threads++;
651         }
652         if (down_interruptible(&prestart_sem))
653                 pr_err("  down interruptible failed\n");
654         for (i = 0; i < tcount; i++)
655                 up(&startup_sem);
656         for (i = 0; i < tcount; i++) {
657                 if (IS_ERR(tdata[i].task))
658                         continue;
659                 if ((err = kthread_stop(tdata[i].task))) {
660                         pr_warn("Test failed: thread %d returned: %d\n",
661                                 i, err);
662                         failed_threads++;
663                 }
664         }
665         rhashtable_destroy(&ht);
666         vfree(tdata);
667         vfree(objs);
668
669         /*
670          * rhltable_remove is very expensive, default values can cause test
671          * to run for 2 minutes or more,  use a smaller number instead.
672          */
673         err = test_rhltable(entries / 16);
674         pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
675                 started_threads, failed_threads, err);
676         return 0;
677 }
678
679 static void __exit test_rht_exit(void)
680 {
681 }
682
683 module_init(test_rht_init);
684 module_exit(test_rht_exit);
685
686 MODULE_LICENSE("GPL v2");