diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c index b2957540d3c722d5c7b3d9f94e5b5a1d6c9d7975..6893e57e6782e2bca4e67d88554b3ebec4b06a41 100644 --- a/lib/test_rhashtable.c +++ b/lib/test_rhashtable.c @@ -1,14 +1,9 @@ /* * Resizable, Scalable, Concurrent Hash Table * - * Copyright (c) 2014 Thomas Graf + * Copyright (c) 2014-2015 Thomas Graf * Copyright (c) 2008-2014 Patrick McHardy * - * 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 * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. @@ -26,20 +21,37 @@ #include #include +#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)"); -#define TEST_HT_SIZE 8 -#define TEST_ENTRIES 2048 -#define TEST_PTR ((void *) 0xdeadbeef) -#define TEST_NEXPANDS 4 +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 { - void *ptr; int value; struct rhash_head node; }; -static const struct rhashtable_params test_rht_params = { - .nelem_hint = TEST_HT_SIZE, +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), @@ -51,11 +63,14 @@ static int __init test_rht_lookup(struct rhashtable *ht) { unsigned int i; - for (i = 0; i < TEST_ENTRIES * 2; 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) { @@ -66,9 +81,9 @@ static int __init test_rht_lookup(struct rhashtable *ht) key); return -EEXIST; } else if (expected && obj) { - if (obj->ptr != TEST_PTR || obj->value != i) { - pr_warn("Test failed: Lookup value mismatch %p!=%p, %u!=%u\n", - obj->ptr, TEST_PTR, obj->value, i); + if (obj->value != i) { + pr_warn("Test failed: Lookup value mismatch %u!=%u\n", + obj->value, i); return -EINVAL; } } @@ -77,129 +92,146 @@ static int __init test_rht_lookup(struct rhashtable *ht) 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 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; + err = rhashtable_walk_init(ht, &hti); + if (err) { + pr_warn("Test failed: allocation error"); + return; + } - if (!quiet) - pr_info(" [%#4x/%u]", i, tbl->size); + err = rhashtable_walk_start(&hti); + if (err && err != -EAGAIN) { + pr_warn("Test failed: iterator failed: %d\n", err); + return; + } - rht_for_each_entry_rcu(obj, pos, tbl, i, node) { - cnt++; - total++; - if (!quiet) - pr_cont(" [%p],", obj); + 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; } - rht_for_each_entry_rcu(obj, pos, tbl, i, node) - rcu_cnt++; - - if (rcu_cnt != cnt) - pr_warn("Test failed: Chain count mismach %d != %d", - cnt, rcu_cnt); - - if (!quiet) - pr_cont("\n [%#x] first element: %p, chain length: %u\n", - i, tbl->buckets[i], cnt); + total++; } - pr_info(" Traversal complete: counted=%u, nelems=%u, entries=%d\n", - total, atomic_read(&ht->nelems), TEST_ENTRIES); + 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 != TEST_ENTRIES) + if (total != atomic_read(&ht->nelems) || total != entries) 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 rhash_head *pos, *next; int err; - unsigned int i; + unsigned int i, insert_fails = 0; + s64 start, end; /* * 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); - for (i = 0; i < TEST_ENTRIES; i++) { - struct test_obj *obj; - - obj = kzalloc(sizeof(*obj), GFP_KERNEL); - if (!obj) { - err = -ENOMEM; - goto error; - } + pr_info(" Adding %d keys\n", entries); + start = ktime_get_ns(); + for (i = 0; i < entries; i++) { + struct test_obj *obj = &array[i]; - obj->ptr = TEST_PTR; obj->value = i * 2; err = rhashtable_insert_fast(ht, &obj->node, test_rht_params); - if (err) { - kfree(obj); - goto error; + 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_bucket_stats(ht, true); test_rht_lookup(ht); rcu_read_unlock(); - rcu_read_lock(); - test_bucket_stats(ht, true); - rcu_read_unlock(); + test_bucket_stats(ht); - pr_info(" Deleting %d keys\n", TEST_ENTRIES); - for (i = 0; i < TEST_ENTRIES; i++) { + pr_info(" Deleting %d keys\n", entries); + for (i = 0; i < entries; i++) { u32 key = i * 2; - obj = rhashtable_lookup_fast(ht, &key, test_rht_params); - BUG_ON(!obj); + 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); - kfree(obj); + rhashtable_remove_fast(ht, &obj->node, test_rht_params); + } } - return 0; - -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); + end = ktime_get_ns(); + pr_info(" Duration of test: %lld ns\n", end - start); - return err; + return end - start; } static struct rhashtable ht; static int __init test_rht_init(void) { - int err; + int i, err; + u64 total_time = 0; - pr_info("Running resizable hashtable tests...\n"); + entries = min(entries, MAX_ENTRIES); - err = rhashtable_init(&ht, &test_rht_params); - if (err < 0) { - pr_warn("Test failed: Unable to initialize hashtable: %d\n", - err); - return err; - } + test_rht_params.automatic_shrinking = shrinking; + test_rht_params.max_size = max_size; + test_rht_params.nelem_hint = size; - err = test_rhashtable(&ht); + pr_info("Running rhashtable test nelem=%d, max_size=%d, shrinking=%d\n", + size, max_size, shrinking); - rhashtable_destroy(&ht); + for (i = 0; i < runs; i++) { + s64 time; - return err; + 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; + } + + pr_info("Average test time: %llu\n", total_time / runs); + + return 0; } static void __exit test_rht_exit(void)