/* * Resizable, Scalable, Concurrent Hash Table * * Copyright (c) 2014-2015 Thomas Graf <tgraf@suug.ch> * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ /************************************************************************** * Self Test **************************************************************************/ #include <linux/init.h>#include <linux/jhash.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/rcupdate.h>#include <linux/rhashtable.h>#include <linux/slab.h> #define MAX_ENTRIES	1000000#define TEST_INSERT_FAIL INT_MAX static int entries = 50000;module_param(entries, int, 0);MODULE_PARM_DESC(entries, "Number of entries to add (default: 50000)"); static int runs = 4;module_param(runs, int, 0);MODULE_PARM_DESC(runs, "Number of test runs per variant (default: 4)"); static int max_size = 65536;module_param(max_size, int, 0);MODULE_PARM_DESC(runs, "Maximum table size (default: 65536)"); static bool shrinking = false;module_param(shrinking, bool, 0);MODULE_PARM_DESC(shrinking, "Enable automatic shrinking (default: off)"); static int size = 8;module_param(size, int, 0);MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)"); struct test_obj {	int			value;	struct rhash_head	node;}; static struct test_obj array[MAX_ENTRIES]; static struct rhashtable_params test_rht_params = {	.head_offset = offsetof(struct test_obj, node),	.key_offset = offsetof(struct test_obj, value),	.key_len = sizeof(int),	.hashfn = jhash,	.nulls_base = (3U << RHT_BASE_SHIFT),}; static int __init test_rht_lookup(struct rhashtable *ht){	unsigned int i; 	for (i = 0; i < entries * 2; i++) {		struct test_obj *obj;		bool expected = !(i % 2);		u32 key = i; 		if (array[i / 2].value == TEST_INSERT_FAIL)			expected = false; 		obj = rhashtable_lookup_fast(ht, &key, test_rht_params); 		if (expected && !obj) {			pr_warn("Test failed: Could not find key %u\n", key);			return -ENOENT;		} else if (!expected && obj) {			pr_warn("Test failed: Unexpected entry found for key %u\n",				key);			return -EEXIST;		} else if (expected && obj) {			if (obj->value != i) {				pr_warn("Test failed: Lookup value mismatch %u!=%u\n",					obj->value, i);				return -EINVAL;			}		}	} 	return 0;} static void test_bucket_stats(struct rhashtable *ht){	unsigned int err, total = 0, chain_len = 0;	struct rhashtable_iter hti;	struct rhash_head *pos; 	err = rhashtable_walk_init(ht, &hti);	if (err) {		pr_warn("Test failed: allocation error");		return;	} 	err = rhashtable_walk_start(&hti);	if (err && err != -EAGAIN) {		pr_warn("Test failed: iterator failed: %d\n", err);		return;	} 	while ((pos = rhashtable_walk_next(&hti))) {		if (PTR_ERR(pos) == -EAGAIN) {			pr_info("Info: encountered resize\n");			chain_len++;			continue;		} else if (IS_ERR(pos)) {			pr_warn("Test failed: rhashtable_walk_next() error: %ld\n",				PTR_ERR(pos));			break;		} 		total++;	} 	rhashtable_walk_stop(&hti);	rhashtable_walk_exit(&hti); 	pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d, table-jumps=%u\n",		total, atomic_read(&ht->nelems), entries, chain_len); 	if (total != atomic_read(&ht->nelems) || total != entries)		pr_warn("Test failed: Total count mismatch ^^^");} static s64 __init test_rhashtable(struct rhashtable *ht){	struct test_obj *obj;	int err;	unsigned int i, insert_fails = 0;	s64 start, end; 	/*	 * Insertion Test:	 * Insert entries into table with all keys even numbers	 */	pr_info("  Adding %d keys\n", entries);	start = ktime_get_ns();	for (i = 0; i < entries; i++) {		struct test_obj *obj = &array[i]; 		obj->value = i * 2; 		err = rhashtable_insert_fast(ht, &obj->node, test_rht_params);		if (err == -ENOMEM || err == -EBUSY) {			/* Mark failed inserts but continue */			obj->value = TEST_INSERT_FAIL;			insert_fails++;		} else if (err) {			return err;		}	} 	if (insert_fails)		pr_info("  %u insertions failed due to memory pressure\n",			insert_fails); 	test_bucket_stats(ht);	rcu_read_lock();	test_rht_lookup(ht);	rcu_read_unlock(); 	test_bucket_stats(ht); 	pr_info("  Deleting %d keys\n", entries);	for (i = 0; i < entries; i++) {		u32 key = i * 2; 		if (array[i].value != TEST_INSERT_FAIL) {			obj = rhashtable_lookup_fast(ht, &key, test_rht_params);			BUG_ON(!obj); 			rhashtable_remove_fast(ht, &obj->node, test_rht_params);		}	} 	end = ktime_get_ns();	pr_info("  Duration of test: %lld ns\n", end - start); 	return end - start;} static struct rhashtable ht; static int __init test_rht_init(void){	int i, err;	u64 total_time = 0; 	entries = min(entries, MAX_ENTRIES); 	test_rht_params.automatic_shrinking = shrinking;	test_rht_params.max_size = max_size;	test_rht_params.nelem_hint = size; 	pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n",		size, max_size, shrinking); 	for (i = 0; i < runs; i++) {		s64 time; 		pr_info("Test %02d:\n", i);		memset(&array, 0, sizeof(array));		err = rhashtable_init(&ht, &test_rht_params);		if (err < 0) {			pr_warn("Test failed: Unable to initialize hashtable: %d\n",				err);			continue;		} 		time = test_rhashtable(&ht);		rhashtable_destroy(&ht);		if (time < 0) {			pr_warn("Test failed: return code %lld\n", time);			return -EINVAL;		} 		total_time += time;	} 	do_div(total_time, runs);	pr_info("Average test time: %llu\n", total_time); 	return 0;} static void __exit test_rht_exit(void){} module_init(test_rht_init);module_exit(test_rht_exit); MODULE_LICENSE("GPL v2");