Commit 10308220 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'rhashtable-test' 



Thomas Graf says:

====================
rhashtable self-test improvements

This series improves the rhashtable self-test to:
  * Avoid allocation of test objects
  * Measure the time of test runs
  * Use the iterator to walk the table for consistency
  * Account for failed insertions due to memory pressure or
    utilization pressure
  * Ignore failed insertions when checking for consistency
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 7a852021 67b7cbf4

lib/test_rhashtable.c

+123 −91
Original line number Original line Diff line number Diff line 
/*

/*

 * Resizable, Scalable, Concurrent Hash Table

 * Resizable, Scalable, Concurrent Hash Table

 *

 *

 * Copyright (c) 2014 Thomas Graf <tgraf@suug.ch>

 * Copyright (c) 2014-2015 Thomas Graf <tgraf@suug.ch>

 * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>

 * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>

 *

 *

 * Based on the following paper:

 * https://www.usenix.org/legacy/event/atc11/tech/final_files/Triplett.pdf

 *

 * Code partially derived from nft_hash

 *

 * This program is free software; you can redistribute it and/or modify

 * 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

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 * published by the Free Software Foundation.
@@ -26,20 +21,37 @@ 
#include <linux/rhashtable.h>

#include <linux/rhashtable.h>

#include <linux/slab.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)");





#define TEST_HT_SIZE	8

static int size = 8;

#define TEST_ENTRIES	2048

module_param(size, int, 0);

#define TEST_PTR	((void *) 0xdeadbeef)

MODULE_PARM_DESC(size, "Initial size hint of table (default: 8)");

#define TEST_NEXPANDS	4





struct test_obj {

struct test_obj {

	void			*ptr;

	int			value;

	int			value;

	struct rhash_head	node;

	struct rhash_head	node;

};

};





static const struct rhashtable_params test_rht_params = {

static struct test_obj array[MAX_ENTRIES];

	.nelem_hint = TEST_HT_SIZE,



static struct rhashtable_params test_rht_params = {

	.head_offset = offsetof(struct test_obj, node),

	.head_offset = offsetof(struct test_obj, node),

	.key_offset = offsetof(struct test_obj, value),

	.key_offset = offsetof(struct test_obj, value),

	.key_len = sizeof(int),

	.key_len = sizeof(int),
@@ -51,11 +63,14 @@ static int __init test_rht_lookup(struct rhashtable *ht) 
{

{

	unsigned int i;

	unsigned int i;





	for (i = 0; i < TEST_ENTRIES * 2; i++) {

	for (i = 0; i < entries * 2; i++) {

		struct test_obj *obj;

		struct test_obj *obj;

		bool expected = !(i % 2);

		bool expected = !(i % 2);

		u32 key = i;

		u32 key = i;





		if (array[i / 2].value == TEST_INSERT_FAIL)

			expected = false;



		obj = rhashtable_lookup_fast(ht, &key, test_rht_params);

		obj = rhashtable_lookup_fast(ht, &key, test_rht_params);





		if (expected && !obj) {

		if (expected && !obj) {
@@ -66,9 +81,9 @@ static int __init test_rht_lookup(struct rhashtable *ht) 
				key);

				key);

			return -EEXIST;

			return -EEXIST;

		} else if (expected && obj) {

		} else if (expected && obj) {

			if (obj->ptr != TEST_PTR || obj->value != i) {

			if (obj->value != i) {

				pr_warn("Test failed: Lookup value mismatch %p!=%p, %u!=%u\n",

				pr_warn("Test failed: Lookup value mismatch %u!=%u\n",

					obj->ptr, TEST_PTR, obj->value, i);

					obj->value, i);

				return -EINVAL;

				return -EINVAL;

			}

			}

		}

		}
@@ -77,129 +92,146 @@ static int __init test_rht_lookup(struct rhashtable *ht) 
	return 0;

	return 0;

}

}





static void test_bucket_stats(struct rhashtable *ht, bool quiet)

static void test_bucket_stats(struct rhashtable *ht)

{

{

	unsigned int cnt, rcu_cnt, i, total = 0;

	unsigned int err, total = 0, chain_len = 0;

	struct rhashtable_iter hti;

	struct rhash_head *pos;

	struct rhash_head *pos;

	struct test_obj *obj;

	struct bucket_table *tbl;



	tbl = rht_dereference_rcu(ht->tbl, ht);

	for (i = 0; i < tbl->size; i++) {

		rcu_cnt = cnt = 0;



		if (!quiet)

			pr_info(" [%#4x/%u]", i, tbl->size);





		rht_for_each_entry_rcu(obj, pos, tbl, i, node) {

	err = rhashtable_walk_init(ht, &hti);

			cnt++;

	if (err) {

			total++;

		pr_warn("Test failed: allocation error");

			if (!quiet)

		return;

				pr_cont(" [%p],", obj);

	}

	}





		rht_for_each_entry_rcu(obj, pos, tbl, i, node)

	err = rhashtable_walk_start(&hti);

			rcu_cnt++;

	if (err && err != -EAGAIN) {

		pr_warn("Test failed: iterator failed: %d\n", err);

		return;

	}





		if (rcu_cnt != cnt)

	while ((pos = rhashtable_walk_next(&hti))) {

			pr_warn("Test failed: Chain count mismach %d != %d",

		if (PTR_ERR(pos) == -EAGAIN) {

				cnt, rcu_cnt);

			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;

		}





		if (!quiet)

		total++;

			pr_cont("\n  [%#x] first element: %p, chain length: %u\n",

				i, tbl->buckets[i], cnt);

	}

	}





	pr_info("  Traversal complete: counted=%u, nelems=%u, entries=%d\n",

	rhashtable_walk_stop(&hti);

		total, atomic_read(&ht->nelems), TEST_ENTRIES);

	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 != TEST_ENTRIES)

	if (total != atomic_read(&ht->nelems) || total != entries)

		pr_warn("Test failed: Total count mismatch ^^^");

		pr_warn("Test failed: Total count mismatch ^^^");

}

}





static int __init test_rhashtable(struct rhashtable *ht)

static s64 __init test_rhashtable(struct rhashtable *ht)

{

{

	struct bucket_table *tbl;

	struct test_obj *obj;

	struct test_obj *obj;

	struct rhash_head *pos, *next;

	int err;

	int err;

	unsigned int i;

	unsigned int i, insert_fails = 0;

	s64 start, end;





	/*

	/*

	 * Insertion Test:

	 * Insertion Test:

	 * Insert TEST_ENTRIES into table with all keys even numbers

	 * Insert entries into table with all keys even numbers

	 */

	 */

	pr_info("  Adding %d keys\n", TEST_ENTRIES);

	pr_info("  Adding %d keys\n", entries);

	for (i = 0; i < TEST_ENTRIES; i++) {

	start = ktime_get_ns();

		struct test_obj *obj;

	for (i = 0; i < entries; i++) {

		struct test_obj *obj = &array[i];





		obj = kzalloc(sizeof(*obj), GFP_KERNEL);

		if (!obj) {

			err = -ENOMEM;

			goto error;

		}



		obj->ptr = TEST_PTR;

		obj->value = i * 2;

		obj->value = i * 2;





		err = rhashtable_insert_fast(ht, &obj->node, test_rht_params);

		err = rhashtable_insert_fast(ht, &obj->node, test_rht_params);

		if (err) {

		if (err == -ENOMEM || err == -EBUSY) {

			kfree(obj);

			/* Mark failed inserts but continue */

			goto error;

			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();

	rcu_read_lock();

	test_bucket_stats(ht, true);

	test_rht_lookup(ht);

	test_rht_lookup(ht);

	rcu_read_unlock();

	rcu_read_unlock();





	rcu_read_lock();

	test_bucket_stats(ht);

	test_bucket_stats(ht, true);

	rcu_read_unlock();





	pr_info("  Deleting %d keys\n", TEST_ENTRIES);

	pr_info("  Deleting %d keys\n", entries);

	for (i = 0; i < TEST_ENTRIES; i++) {

	for (i = 0; i < entries; i++) {

		u32 key = i * 2;

		u32 key = i * 2;





		if (array[i].value != TEST_INSERT_FAIL) {

			obj = rhashtable_lookup_fast(ht, &key, test_rht_params);

			obj = rhashtable_lookup_fast(ht, &key, test_rht_params);

			BUG_ON(!obj);

			BUG_ON(!obj);





			rhashtable_remove_fast(ht, &obj->node, test_rht_params);

			rhashtable_remove_fast(ht, &obj->node, test_rht_params);

		kfree(obj);

		}

	}

	}





	return 0;

	end = ktime_get_ns();



	pr_info("  Duration of test: %lld ns\n", end - start);

error:

	tbl = rht_dereference_rcu(ht->tbl, ht);

	for (i = 0; i < tbl->size; i++)

		rht_for_each_entry_safe(obj, pos, next, tbl, i, node)

			kfree(obj);





	return err;

	return end - start;

}

}





static struct rhashtable ht;

static struct rhashtable ht;





static int __init test_rht_init(void)

static int __init test_rht_init(void)

{

{

	int err;

	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 resizable hashtable tests...\n");

	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);

		err = rhashtable_init(&ht, &test_rht_params);

		if (err < 0) {

		if (err < 0) {

			pr_warn("Test failed: Unable to initialize hashtable: %d\n",

			pr_warn("Test failed: Unable to initialize hashtable: %d\n",

				err);

				err);

		return err;

			continue;

		}

		}





	err = test_rhashtable(&ht);

		time = test_rhashtable(&ht);



		rhashtable_destroy(&ht);

		rhashtable_destroy(&ht);

		if (time < 0) {

			pr_warn("Test failed: return code %lld\n", time);

			return -EINVAL;

		}





	return err;

		total_time += time;

	}



	pr_info("Average test time: %llu\n", total_time / runs);



	return 0;

}

}





static void __exit test_rht_exit(void)

static void __exit test_rht_exit(void)

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