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v5.14.15
  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
 29static int parm_entries = 50000;
 30module_param(parm_entries, int, 0);
 31MODULE_PARM_DESC(parm_entries, "Number of entries to add (default: 50000)");
 32
 33static int runs = 4;
 34module_param(runs, int, 0);
 35MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)");
 36
 37static int max_size = 0;
 38module_param(max_size, int, 0);
 39MODULE_PARM_DESC(max_size, "Maximum table size (default: calculated)");
 40
 41static bool shrinking = false;
 42module_param(shrinking, bool, 0);
 43MODULE_PARM_DESC(shrinking, "Enable automatic shrinking (default: off)");
 44
 45static int size = 8;
 46module_param(size, int, 0);
 47MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)");
 48
 49static int tcount = 10;
 50module_param(tcount, int, 0);
 51MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");
 52
 53static bool enomem_retry = false;
 54module_param(enomem_retry, bool, 0);
 55MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");
 56
 57struct test_obj_val {
 58	int	id;
 59	int	tid;
 60};
 61
 62struct test_obj {
 63	struct test_obj_val	value;
 64	struct rhash_head	node;
 65};
 66
 67struct test_obj_rhl {
 68	struct test_obj_val	value;
 69	struct rhlist_head	list_node;
 70};
 71
 72struct thread_data {
 73	unsigned int entries;
 74	int id;
 75	struct task_struct *task;
 76	struct test_obj *objs;
 77};
 78
 79static 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
 86static 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
 94static 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
101static 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
112static atomic_t startup_count;
113static DECLARE_WAIT_QUEUE_HEAD(startup_wait);
114
115static 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
137static 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
175static 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
208static 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
266static struct rhashtable ht;
267static struct rhltable rhlt;
268
269static 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);
442out_free:
443	vfree(rhl_test_objects);
444	vfree(obj_in_table);
445	return ret;
446}
447
448static 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
485static 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
534static 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
573skip_print:
574	rhltable_destroy(rhlt);
575	kfree(rhlt);
576
577	return 0;
578}
579
580static 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
602static 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
632static 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	}
689out:
690	while (!kthread_should_stop()) {
691		set_current_state(TASK_INTERRUPTIBLE);
692		schedule();
693	}
694	return err;
695}
696
697static 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
822static void __exit test_rht_exit(void)
823{
824}
825
826module_init(test_rht_init);
827module_exit(test_rht_exit);
828
 
829MODULE_LICENSE("GPL v2");
v6.13.7
  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/rcupdate_wait.h>
 20#include <linux/rhashtable.h>
 21#include <linux/slab.h>
 22#include <linux/sched.h>
 23#include <linux/random.h>
 24#include <linux/vmalloc.h>
 25#include <linux/wait.h>
 26
 27#define MAX_ENTRIES	1000000
 28#define TEST_INSERT_FAIL INT_MAX
 29
 30static int parm_entries = 50000;
 31module_param(parm_entries, int, 0);
 32MODULE_PARM_DESC(parm_entries, "Number of entries to add (default: 50000)");
 33
 34static int runs = 4;
 35module_param(runs, int, 0);
 36MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)");
 37
 38static int max_size = 0;
 39module_param(max_size, int, 0);
 40MODULE_PARM_DESC(max_size, "Maximum table size (default: calculated)");
 41
 42static bool shrinking = false;
 43module_param(shrinking, bool, 0);
 44MODULE_PARM_DESC(shrinking, "Enable automatic shrinking (default: off)");
 45
 46static int size = 8;
 47module_param(size, int, 0);
 48MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)");
 49
 50static int tcount = 10;
 51module_param(tcount, int, 0);
 52MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");
 53
 54static bool enomem_retry = false;
 55module_param(enomem_retry, bool, 0);
 56MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");
 57
 58struct test_obj_val {
 59	int	id;
 60	int	tid;
 61};
 62
 63struct test_obj {
 64	struct test_obj_val	value;
 65	struct rhash_head	node;
 66};
 67
 68struct test_obj_rhl {
 69	struct test_obj_val	value;
 70	struct rhlist_head	list_node;
 71};
 72
 73struct thread_data {
 74	unsigned int entries;
 75	int id;
 76	struct task_struct *task;
 77	struct test_obj *objs;
 78};
 79
 80static u32 my_hashfn(const void *data, u32 len, u32 seed)
 81{
 82	const struct test_obj_rhl *obj = data;
 83
 84	return (obj->value.id % 10);
 85}
 86
 87static int my_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
 88{
 89	const struct test_obj_rhl *test_obj = obj;
 90	const struct test_obj_val *val = arg->key;
 91
 92	return test_obj->value.id - val->id;
 93}
 94
 95static struct rhashtable_params test_rht_params = {
 96	.head_offset = offsetof(struct test_obj, node),
 97	.key_offset = offsetof(struct test_obj, value),
 98	.key_len = sizeof(struct test_obj_val),
 99	.hashfn = jhash,
100};
101
102static struct rhashtable_params test_rht_params_dup = {
103	.head_offset = offsetof(struct test_obj_rhl, list_node),
104	.key_offset = offsetof(struct test_obj_rhl, value),
105	.key_len = sizeof(struct test_obj_val),
106	.hashfn = jhash,
107	.obj_hashfn = my_hashfn,
108	.obj_cmpfn = my_cmpfn,
109	.nelem_hint = 128,
110	.automatic_shrinking = false,
111};
112
113static atomic_t startup_count;
114static DECLARE_WAIT_QUEUE_HEAD(startup_wait);
115
116static int insert_retry(struct rhashtable *ht, struct test_obj *obj,
117                        const struct rhashtable_params params)
118{
119	int err, retries = -1, enomem_retries = 0;
120
121	do {
122		retries++;
123		cond_resched();
124		err = rhashtable_insert_fast(ht, &obj->node, params);
125		if (err == -ENOMEM && enomem_retry) {
126			enomem_retries++;
127			err = -EBUSY;
128		}
129	} while (err == -EBUSY);
130
131	if (enomem_retries)
132		pr_info(" %u insertions retried after -ENOMEM\n",
133			enomem_retries);
134
135	return err ? : retries;
136}
137
138static int __init test_rht_lookup(struct rhashtable *ht, struct test_obj *array,
139				  unsigned int entries)
140{
141	unsigned int i;
142
143	for (i = 0; i < entries; i++) {
144		struct test_obj *obj;
145		bool expected = !(i % 2);
146		struct test_obj_val key = {
147			.id = i,
148		};
149
150		if (array[i / 2].value.id == TEST_INSERT_FAIL)
151			expected = false;
152
153		obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
154
155		if (expected && !obj) {
156			pr_warn("Test failed: Could not find key %u\n", key.id);
157			return -ENOENT;
158		} else if (!expected && obj) {
159			pr_warn("Test failed: Unexpected entry found for key %u\n",
160				key.id);
161			return -EEXIST;
162		} else if (expected && obj) {
163			if (obj->value.id != i) {
164				pr_warn("Test failed: Lookup value mismatch %u!=%u\n",
165					obj->value.id, i);
166				return -EINVAL;
167			}
168		}
169
170		cond_resched_rcu();
171	}
172
173	return 0;
174}
175
176static void test_bucket_stats(struct rhashtable *ht, unsigned int entries)
177{
178	unsigned int total = 0, chain_len = 0;
179	struct rhashtable_iter hti;
180	struct rhash_head *pos;
181
182	rhashtable_walk_enter(ht, &hti);
183	rhashtable_walk_start(&hti);
184
185	while ((pos = rhashtable_walk_next(&hti))) {
186		if (PTR_ERR(pos) == -EAGAIN) {
187			pr_info("Info: encountered resize\n");
188			chain_len++;
189			continue;
190		} else if (IS_ERR(pos)) {
191			pr_warn("Test failed: rhashtable_walk_next() error: %ld\n",
192				PTR_ERR(pos));
193			break;
194		}
195
196		total++;
197	}
198
199	rhashtable_walk_stop(&hti);
200	rhashtable_walk_exit(&hti);
201
202	pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d, table-jumps=%u\n",
203		total, atomic_read(&ht->nelems), entries, chain_len);
204
205	if (total != atomic_read(&ht->nelems) || total != entries)
206		pr_warn("Test failed: Total count mismatch ^^^");
207}
208
209static s64 __init test_rhashtable(struct rhashtable *ht, struct test_obj *array,
210				  unsigned int entries)
211{
212	struct test_obj *obj;
213	int err;
214	unsigned int i, insert_retries = 0;
215	s64 start, end;
216
217	/*
218	 * Insertion Test:
219	 * Insert entries into table with all keys even numbers
220	 */
221	pr_info("  Adding %d keys\n", entries);
222	start = ktime_get_ns();
223	for (i = 0; i < entries; i++) {
224		struct test_obj *obj = &array[i];
225
226		obj->value.id = i * 2;
227		err = insert_retry(ht, obj, test_rht_params);
228		if (err > 0)
229			insert_retries += err;
230		else if (err)
231			return err;
232	}
233
234	if (insert_retries)
235		pr_info("  %u insertions retried due to memory pressure\n",
236			insert_retries);
237
238	test_bucket_stats(ht, entries);
239	rcu_read_lock();
240	test_rht_lookup(ht, array, entries);
241	rcu_read_unlock();
242
243	test_bucket_stats(ht, entries);
244
245	pr_info("  Deleting %d keys\n", entries);
246	for (i = 0; i < entries; i++) {
247		struct test_obj_val key = {
248			.id = i * 2,
249		};
250
251		if (array[i].value.id != TEST_INSERT_FAIL) {
252			obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
253			BUG_ON(!obj);
254
255			rhashtable_remove_fast(ht, &obj->node, test_rht_params);
256		}
257
258		cond_resched();
259	}
260
261	end = ktime_get_ns();
262	pr_info("  Duration of test: %lld ns\n", end - start);
263
264	return end - start;
265}
266
267static struct rhashtable ht;
268static struct rhltable rhlt;
269
270static int __init test_rhltable(unsigned int entries)
271{
272	struct test_obj_rhl *rhl_test_objects;
273	unsigned long *obj_in_table;
274	unsigned int i, j, k;
275	int ret, err;
276
277	if (entries == 0)
278		entries = 1;
279
280	rhl_test_objects = vzalloc(array_size(entries,
281					      sizeof(*rhl_test_objects)));
282	if (!rhl_test_objects)
283		return -ENOMEM;
284
285	ret = -ENOMEM;
286	obj_in_table = vzalloc(array_size(sizeof(unsigned long),
287					  BITS_TO_LONGS(entries)));
288	if (!obj_in_table)
289		goto out_free;
290
291	err = rhltable_init(&rhlt, &test_rht_params);
292	if (WARN_ON(err))
293		goto out_free;
294
295	k = get_random_u32();
296	ret = 0;
297	for (i = 0; i < entries; i++) {
298		rhl_test_objects[i].value.id = k;
299		err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
300				      test_rht_params);
301		if (WARN(err, "error %d on element %d\n", err, i))
302			break;
303		if (err == 0)
304			set_bit(i, obj_in_table);
305	}
306
307	if (err)
308		ret = err;
309
310	pr_info("test %d add/delete pairs into rhlist\n", entries);
311	for (i = 0; i < entries; i++) {
312		struct rhlist_head *h, *pos;
313		struct test_obj_rhl *obj;
314		struct test_obj_val key = {
315			.id = k,
316		};
317		bool found;
318
319		rcu_read_lock();
320		h = rhltable_lookup(&rhlt, &key, test_rht_params);
321		if (WARN(!h, "key not found during iteration %d of %d", i, entries)) {
322			rcu_read_unlock();
323			break;
324		}
325
326		if (i) {
327			j = i - 1;
328			rhl_for_each_entry_rcu(obj, pos, h, list_node) {
329				if (WARN(pos == &rhl_test_objects[j].list_node, "old element found, should be gone"))
330					break;
331			}
332		}
333
334		cond_resched_rcu();
335
336		found = false;
337
338		rhl_for_each_entry_rcu(obj, pos, h, list_node) {
339			if (pos == &rhl_test_objects[i].list_node) {
340				found = true;
341				break;
342			}
343		}
344
345		rcu_read_unlock();
346
347		if (WARN(!found, "element %d not found", i))
348			break;
349
350		err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
351		WARN(err, "rhltable_remove: err %d for iteration %d\n", err, i);
352		if (err == 0)
353			clear_bit(i, obj_in_table);
354	}
355
356	if (ret == 0 && err)
357		ret = err;
358
359	for (i = 0; i < entries; i++) {
360		WARN(test_bit(i, obj_in_table), "elem %d allegedly still present", i);
361
362		err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
363				      test_rht_params);
364		if (WARN(err, "error %d on element %d\n", err, i))
365			break;
366		if (err == 0)
367			set_bit(i, obj_in_table);
368	}
369
370	pr_info("test %d random rhlist add/delete operations\n", entries);
371	for (j = 0; j < entries; j++) {
372		u32 i = get_random_u32_below(entries);
373		u32 prand = get_random_u32_below(4);
374
375		cond_resched();
376
 
 
 
 
 
 
 
 
377		err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
378		if (test_bit(i, obj_in_table)) {
379			clear_bit(i, obj_in_table);
380			if (WARN(err, "cannot remove element at slot %d", i))
381				continue;
382		} else {
383			if (WARN(err != -ENOENT, "removed non-existent element %d, error %d not %d",
384			     i, err, -ENOENT))
385				continue;
386		}
387
388		if (prand & 1) {
389			err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
390			if (err == 0) {
391				if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
392					continue;
393			} else {
394				if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
395					continue;
396			}
 
 
 
 
 
 
 
 
397		}
398
399		if (prand & 2) {
400			i = get_random_u32_below(entries);
401			if (test_bit(i, obj_in_table)) {
402				err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
403				WARN(err, "cannot remove element at slot %d", i);
404				if (err == 0)
405					clear_bit(i, obj_in_table);
406			} else {
407				err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
408				WARN(err, "failed to insert object %d", i);
409				if (err == 0)
410					set_bit(i, obj_in_table);
411			}
412		}
413	}
414
415	for (i = 0; i < entries; i++) {
416		cond_resched();
417		err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
418		if (test_bit(i, obj_in_table)) {
419			if (WARN(err, "cannot remove element at slot %d", i))
420				continue;
421		} else {
422			if (WARN(err != -ENOENT, "removed non-existent element, error %d not %d",
423				 err, -ENOENT))
424				continue;
425		}
426	}
427
428	rhltable_destroy(&rhlt);
429out_free:
430	vfree(rhl_test_objects);
431	vfree(obj_in_table);
432	return ret;
433}
434
435static int __init test_rhashtable_max(struct test_obj *array,
436				      unsigned int entries)
437{
438	unsigned int i;
439	int err;
440
441	test_rht_params.max_size = roundup_pow_of_two(entries / 8);
442	err = rhashtable_init(&ht, &test_rht_params);
443	if (err)
444		return err;
445
446	for (i = 0; i < ht.max_elems; i++) {
447		struct test_obj *obj = &array[i];
448
449		obj->value.id = i * 2;
450		err = insert_retry(&ht, obj, test_rht_params);
451		if (err < 0)
 
 
452			return err;
453	}
454
455	err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
456	if (err == -E2BIG) {
457		err = 0;
458	} else {
459		pr_info("insert element %u should have failed with %d, got %d\n",
460				ht.max_elems, -E2BIG, err);
461		if (err == 0)
462			err = -1;
463	}
464
465	rhashtable_destroy(&ht);
466
467	return err;
468}
469
470static unsigned int __init print_ht(struct rhltable *rhlt)
471{
472	struct rhashtable *ht;
473	const struct bucket_table *tbl;
474	char buff[512] = "";
475	int offset = 0;
476	unsigned int i, cnt = 0;
477
478	ht = &rhlt->ht;
479	/* Take the mutex to avoid RCU warning */
480	mutex_lock(&ht->mutex);
481	tbl = rht_dereference(ht->tbl, ht);
482	for (i = 0; i < tbl->size; i++) {
483		struct rhash_head *pos, *next;
484		struct test_obj_rhl *p;
485
486		pos = rht_ptr_exclusive(tbl->buckets + i);
487		next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
488
489		if (!rht_is_a_nulls(pos)) {
490			offset += sprintf(buff + offset, "\nbucket[%d] -> ", i);
491		}
492
493		while (!rht_is_a_nulls(pos)) {
494			struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
495			offset += sprintf(buff + offset, "[[");
496			do {
497				pos = &list->rhead;
498				list = rht_dereference(list->next, ht);
499				p = rht_obj(ht, pos);
500
501				offset += sprintf(buff + offset, " val %d (tid=%d)%s", p->value.id, p->value.tid,
502					list? ", " : " ");
503				cnt++;
504			} while (list);
505
506			pos = next,
507			next = !rht_is_a_nulls(pos) ?
508				rht_dereference(pos->next, ht) : NULL;
509
510			offset += sprintf(buff + offset, "]]%s", !rht_is_a_nulls(pos) ? " -> " : "");
511		}
512	}
513	printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
514	mutex_unlock(&ht->mutex);
515
516	return cnt;
517}
518
519static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
520				  int cnt, bool slow)
521{
522	struct rhltable *rhlt;
523	unsigned int i, ret;
524	const char *key;
525	int err = 0;
526
527	rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
528	if (WARN_ON(!rhlt))
529		return -EINVAL;
530
531	err = rhltable_init(rhlt, &test_rht_params_dup);
532	if (WARN_ON(err)) {
533		kfree(rhlt);
534		return err;
535	}
536
537	for (i = 0; i < cnt; i++) {
538		rhl_test_objects[i].value.tid = i;
539		key = rht_obj(&rhlt->ht, &rhl_test_objects[i].list_node.rhead);
540		key += test_rht_params_dup.key_offset;
541
542		if (slow) {
543			err = PTR_ERR(rhashtable_insert_slow(&rhlt->ht, key,
544							     &rhl_test_objects[i].list_node.rhead));
545			if (err == -EAGAIN)
546				err = 0;
547		} else
548			err = rhltable_insert(rhlt,
549					      &rhl_test_objects[i].list_node,
550					      test_rht_params_dup);
551		if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
552			goto skip_print;
553	}
554
555	ret = print_ht(rhlt);
556	WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
557
558skip_print:
559	rhltable_destroy(rhlt);
560	kfree(rhlt);
561
562	return 0;
563}
564
565static int __init test_insert_duplicates_run(void)
566{
567	struct test_obj_rhl rhl_test_objects[3] = {};
568
569	pr_info("test inserting duplicates\n");
570
571	/* two different values that map to same bucket */
572	rhl_test_objects[0].value.id = 1;
573	rhl_test_objects[1].value.id = 21;
574
575	/* and another duplicate with same as [0] value
576	 * which will be second on the bucket list */
577	rhl_test_objects[2].value.id = rhl_test_objects[0].value.id;
578
579	test_insert_dup(rhl_test_objects, 2, false);
580	test_insert_dup(rhl_test_objects, 3, false);
581	test_insert_dup(rhl_test_objects, 2, true);
582	test_insert_dup(rhl_test_objects, 3, true);
583
584	return 0;
585}
586
587static int thread_lookup_test(struct thread_data *tdata)
588{
589	unsigned int entries = tdata->entries;
590	int i, err = 0;
591
592	for (i = 0; i < entries; i++) {
593		struct test_obj *obj;
594		struct test_obj_val key = {
595			.id = i,
596			.tid = tdata->id,
597		};
598
599		obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
600		if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
601			pr_err("  found unexpected object %d-%d\n", key.tid, key.id);
602			err++;
603		} else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
604			pr_err("  object %d-%d not found!\n", key.tid, key.id);
605			err++;
606		} else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
607			pr_err("  wrong object returned (got %d-%d, expected %d-%d)\n",
608			       obj->value.tid, obj->value.id, key.tid, key.id);
609			err++;
610		}
611
612		cond_resched();
613	}
614	return err;
615}
616
617static int threadfunc(void *data)
618{
619	int i, step, err = 0, insert_retries = 0;
620	struct thread_data *tdata = data;
621
622	if (atomic_dec_and_test(&startup_count))
623		wake_up(&startup_wait);
624	if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == -1)) {
625		pr_err("  thread[%d]: interrupted\n", tdata->id);
626		goto out;
627	}
628
629	for (i = 0; i < tdata->entries; i++) {
630		tdata->objs[i].value.id = i;
631		tdata->objs[i].value.tid = tdata->id;
632		err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
633		if (err > 0) {
634			insert_retries += err;
635		} else if (err) {
636			pr_err("  thread[%d]: rhashtable_insert_fast failed\n",
637			       tdata->id);
638			goto out;
639		}
640	}
641	if (insert_retries)
642		pr_info("  thread[%d]: %u insertions retried due to memory pressure\n",
643			tdata->id, insert_retries);
644
645	err = thread_lookup_test(tdata);
646	if (err) {
647		pr_err("  thread[%d]: rhashtable_lookup_test failed\n",
648		       tdata->id);
649		goto out;
650	}
651
652	for (step = 10; step > 0; step--) {
653		for (i = 0; i < tdata->entries; i += step) {
654			if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
655				continue;
656			err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
657			                             test_rht_params);
658			if (err) {
659				pr_err("  thread[%d]: rhashtable_remove_fast failed\n",
660				       tdata->id);
661				goto out;
662			}
663			tdata->objs[i].value.id = TEST_INSERT_FAIL;
664
665			cond_resched();
666		}
667		err = thread_lookup_test(tdata);
668		if (err) {
669			pr_err("  thread[%d]: rhashtable_lookup_test (2) failed\n",
670			       tdata->id);
671			goto out;
672		}
673	}
674out:
675	while (!kthread_should_stop()) {
676		set_current_state(TASK_INTERRUPTIBLE);
677		schedule();
678	}
679	return err;
680}
681
682static int __init test_rht_init(void)
683{
684	unsigned int entries;
685	int i, err, started_threads = 0, failed_threads = 0;
686	u64 total_time = 0;
687	struct thread_data *tdata;
688	struct test_obj *objs;
689
690	if (parm_entries < 0)
691		parm_entries = 1;
692
693	entries = min(parm_entries, MAX_ENTRIES);
694
695	test_rht_params.automatic_shrinking = shrinking;
696	test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
697	test_rht_params.nelem_hint = size;
698
699	objs = vzalloc(array_size(sizeof(struct test_obj),
700				  test_rht_params.max_size + 1));
701	if (!objs)
702		return -ENOMEM;
703
704	pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",
705		size, max_size, shrinking);
706
707	for (i = 0; i < runs; i++) {
708		s64 time;
709
710		pr_info("Test %02d:\n", i);
711		memset(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
712
713		err = rhashtable_init(&ht, &test_rht_params);
714		if (err < 0) {
715			pr_warn("Test failed: Unable to initialize hashtable: %d\n",
716				err);
717			continue;
718		}
719
720		time = test_rhashtable(&ht, objs, entries);
721		rhashtable_destroy(&ht);
722		if (time < 0) {
723			vfree(objs);
724			pr_warn("Test failed: return code %lld\n", time);
725			return -EINVAL;
726		}
727
728		total_time += time;
729	}
730
731	pr_info("test if its possible to exceed max_size %d: %s\n",
732			test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
733			"no, ok" : "YES, failed");
734	vfree(objs);
735
736	do_div(total_time, runs);
737	pr_info("Average test time: %llu\n", total_time);
738
739	test_insert_duplicates_run();
740
741	if (!tcount)
742		return 0;
743
744	pr_info("Testing concurrent rhashtable access from %d threads\n",
745	        tcount);
746	atomic_set(&startup_count, tcount);
747	tdata = vzalloc(array_size(tcount, sizeof(struct thread_data)));
748	if (!tdata)
749		return -ENOMEM;
750	objs  = vzalloc(array3_size(sizeof(struct test_obj), tcount, entries));
751	if (!objs) {
752		vfree(tdata);
753		return -ENOMEM;
754	}
755
756	test_rht_params.max_size = max_size ? :
757	                           roundup_pow_of_two(tcount * entries);
758	err = rhashtable_init(&ht, &test_rht_params);
759	if (err < 0) {
760		pr_warn("Test failed: Unable to initialize hashtable: %d\n",
761			err);
762		vfree(tdata);
763		vfree(objs);
764		return -EINVAL;
765	}
766	for (i = 0; i < tcount; i++) {
767		tdata[i].id = i;
768		tdata[i].entries = entries;
769		tdata[i].objs = objs + i * entries;
770		tdata[i].task = kthread_run(threadfunc, &tdata[i],
771		                            "rhashtable_thrad[%d]", i);
772		if (IS_ERR(tdata[i].task)) {
773			pr_err(" kthread_run failed for thread %d\n", i);
774			atomic_dec(&startup_count);
775		} else {
776			started_threads++;
777		}
778	}
779	if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == 0))
780		pr_err("  wait_event interruptible failed\n");
781	/* count is 0 now, set it to -1 and wake up all threads together */
782	atomic_dec(&startup_count);
783	wake_up_all(&startup_wait);
784	for (i = 0; i < tcount; i++) {
785		if (IS_ERR(tdata[i].task))
786			continue;
787		if ((err = kthread_stop(tdata[i].task))) {
788			pr_warn("Test failed: thread %d returned: %d\n",
789			        i, err);
790			failed_threads++;
791		}
792	}
793	rhashtable_destroy(&ht);
794	vfree(tdata);
795	vfree(objs);
796
797	/*
798	 * rhltable_remove is very expensive, default values can cause test
799	 * to run for 2 minutes or more,  use a smaller number instead.
800	 */
801	err = test_rhltable(entries / 16);
802	pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
803	        started_threads, failed_threads, err);
804	return 0;
805}
806
807static void __exit test_rht_exit(void)
808{
809}
810
811module_init(test_rht_init);
812module_exit(test_rht_exit);
813
814MODULE_DESCRIPTION("Resizable, Scalable, Concurrent Hash Table test module");
815MODULE_LICENSE("GPL v2");