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-rw-r--r--lib/test_rhashtable.c828
1 files changed, 828 insertions, 0 deletions
diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
new file mode 100644
index 000000000..76c607ee6
--- /dev/null
+++ b/lib/test_rhashtable.c
@@ -0,0 +1,828 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Resizable, Scalable, Concurrent Hash Table
+ *
+ * Copyright (c) 2014-2015 Thomas Graf <tgraf@suug.ch>
+ * Copyright (c) 2008-2014 Patrick McHardy <kaber@trash.net>
+ */
+
+/**************************************************************************
+ * Self Test
+ **************************************************************************/
+
+#include <linux/init.h>
+#include <linux/jhash.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/rcupdate.h>
+#include <linux/rhashtable.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/random.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+
+#define MAX_ENTRIES 1000000
+#define TEST_INSERT_FAIL INT_MAX
+
+static int parm_entries = 50000;
+module_param(parm_entries, int, 0);
+MODULE_PARM_DESC(parm_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 = 0;
+module_param(max_size, int, 0);
+MODULE_PARM_DESC(max_size, "Maximum table size (default: calculated)");
+
+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)");
+
+static int tcount = 10;
+module_param(tcount, int, 0);
+MODULE_PARM_DESC(tcount, "Number of threads to spawn (default: 10)");
+
+static bool enomem_retry = false;
+module_param(enomem_retry, bool, 0);
+MODULE_PARM_DESC(enomem_retry, "Retry insert even if -ENOMEM was returned (default: off)");
+
+struct test_obj_val {
+ int id;
+ int tid;
+};
+
+struct test_obj {
+ struct test_obj_val value;
+ struct rhash_head node;
+};
+
+struct test_obj_rhl {
+ struct test_obj_val value;
+ struct rhlist_head list_node;
+};
+
+struct thread_data {
+ unsigned int entries;
+ int id;
+ struct task_struct *task;
+ struct test_obj *objs;
+};
+
+static u32 my_hashfn(const void *data, u32 len, u32 seed)
+{
+ const struct test_obj_rhl *obj = data;
+
+ return (obj->value.id % 10);
+}
+
+static int my_cmpfn(struct rhashtable_compare_arg *arg, const void *obj)
+{
+ const struct test_obj_rhl *test_obj = obj;
+ const struct test_obj_val *val = arg->key;
+
+ return test_obj->value.id - val->id;
+}
+
+static struct rhashtable_params test_rht_params = {
+ .head_offset = offsetof(struct test_obj, node),
+ .key_offset = offsetof(struct test_obj, value),
+ .key_len = sizeof(struct test_obj_val),
+ .hashfn = jhash,
+};
+
+static struct rhashtable_params test_rht_params_dup = {
+ .head_offset = offsetof(struct test_obj_rhl, list_node),
+ .key_offset = offsetof(struct test_obj_rhl, value),
+ .key_len = sizeof(struct test_obj_val),
+ .hashfn = jhash,
+ .obj_hashfn = my_hashfn,
+ .obj_cmpfn = my_cmpfn,
+ .nelem_hint = 128,
+ .automatic_shrinking = false,
+};
+
+static atomic_t startup_count;
+static DECLARE_WAIT_QUEUE_HEAD(startup_wait);
+
+static int insert_retry(struct rhashtable *ht, struct test_obj *obj,
+ const struct rhashtable_params params)
+{
+ int err, retries = -1, enomem_retries = 0;
+
+ do {
+ retries++;
+ cond_resched();
+ err = rhashtable_insert_fast(ht, &obj->node, params);
+ if (err == -ENOMEM && enomem_retry) {
+ enomem_retries++;
+ err = -EBUSY;
+ }
+ } while (err == -EBUSY);
+
+ if (enomem_retries)
+ pr_info(" %u insertions retried after -ENOMEM\n",
+ enomem_retries);
+
+ return err ? : retries;
+}
+
+static int __init test_rht_lookup(struct rhashtable *ht, struct test_obj *array,
+ unsigned int entries)
+{
+ unsigned int i;
+
+ for (i = 0; i < entries; i++) {
+ struct test_obj *obj;
+ bool expected = !(i % 2);
+ struct test_obj_val key = {
+ .id = i,
+ };
+
+ if (array[i / 2].value.id == 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.id);
+ return -ENOENT;
+ } else if (!expected && obj) {
+ pr_warn("Test failed: Unexpected entry found for key %u\n",
+ key.id);
+ return -EEXIST;
+ } else if (expected && obj) {
+ if (obj->value.id != i) {
+ pr_warn("Test failed: Lookup value mismatch %u!=%u\n",
+ obj->value.id, i);
+ return -EINVAL;
+ }
+ }
+
+ cond_resched_rcu();
+ }
+
+ return 0;
+}
+
+static void test_bucket_stats(struct rhashtable *ht, unsigned int entries)
+{
+ unsigned int total = 0, chain_len = 0;
+ struct rhashtable_iter hti;
+ struct rhash_head *pos;
+
+ rhashtable_walk_enter(ht, &hti);
+ rhashtable_walk_start(&hti);
+
+ 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 *array,
+ unsigned int entries)
+{
+ struct test_obj *obj;
+ int err;
+ unsigned int i, insert_retries = 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.id = i * 2;
+ err = insert_retry(ht, obj, test_rht_params);
+ if (err > 0)
+ insert_retries += err;
+ else if (err)
+ return err;
+ }
+
+ if (insert_retries)
+ pr_info(" %u insertions retried due to memory pressure\n",
+ insert_retries);
+
+ test_bucket_stats(ht, entries);
+ rcu_read_lock();
+ test_rht_lookup(ht, array, entries);
+ rcu_read_unlock();
+
+ test_bucket_stats(ht, entries);
+
+ pr_info(" Deleting %d keys\n", entries);
+ for (i = 0; i < entries; i++) {
+ struct test_obj_val key = {
+ .id = i * 2,
+ };
+
+ if (array[i].value.id != TEST_INSERT_FAIL) {
+ obj = rhashtable_lookup_fast(ht, &key, test_rht_params);
+ BUG_ON(!obj);
+
+ rhashtable_remove_fast(ht, &obj->node, test_rht_params);
+ }
+
+ cond_resched();
+ }
+
+ end = ktime_get_ns();
+ pr_info(" Duration of test: %lld ns\n", end - start);
+
+ return end - start;
+}
+
+static struct rhashtable ht;
+static struct rhltable rhlt;
+
+static int __init test_rhltable(unsigned int entries)
+{
+ struct test_obj_rhl *rhl_test_objects;
+ unsigned long *obj_in_table;
+ unsigned int i, j, k;
+ int ret, err;
+
+ if (entries == 0)
+ entries = 1;
+
+ rhl_test_objects = vzalloc(array_size(entries,
+ sizeof(*rhl_test_objects)));
+ if (!rhl_test_objects)
+ return -ENOMEM;
+
+ ret = -ENOMEM;
+ obj_in_table = vzalloc(array_size(sizeof(unsigned long),
+ BITS_TO_LONGS(entries)));
+ if (!obj_in_table)
+ goto out_free;
+
+ err = rhltable_init(&rhlt, &test_rht_params);
+ if (WARN_ON(err))
+ goto out_free;
+
+ k = prandom_u32();
+ ret = 0;
+ for (i = 0; i < entries; i++) {
+ rhl_test_objects[i].value.id = k;
+ err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
+ test_rht_params);
+ if (WARN(err, "error %d on element %d\n", err, i))
+ break;
+ if (err == 0)
+ set_bit(i, obj_in_table);
+ }
+
+ if (err)
+ ret = err;
+
+ pr_info("test %d add/delete pairs into rhlist\n", entries);
+ for (i = 0; i < entries; i++) {
+ struct rhlist_head *h, *pos;
+ struct test_obj_rhl *obj;
+ struct test_obj_val key = {
+ .id = k,
+ };
+ bool found;
+
+ rcu_read_lock();
+ h = rhltable_lookup(&rhlt, &key, test_rht_params);
+ if (WARN(!h, "key not found during iteration %d of %d", i, entries)) {
+ rcu_read_unlock();
+ break;
+ }
+
+ if (i) {
+ j = i - 1;
+ rhl_for_each_entry_rcu(obj, pos, h, list_node) {
+ if (WARN(pos == &rhl_test_objects[j].list_node, "old element found, should be gone"))
+ break;
+ }
+ }
+
+ cond_resched_rcu();
+
+ found = false;
+
+ rhl_for_each_entry_rcu(obj, pos, h, list_node) {
+ if (pos == &rhl_test_objects[i].list_node) {
+ found = true;
+ break;
+ }
+ }
+
+ rcu_read_unlock();
+
+ if (WARN(!found, "element %d not found", i))
+ break;
+
+ err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+ WARN(err, "rhltable_remove: err %d for iteration %d\n", err, i);
+ if (err == 0)
+ clear_bit(i, obj_in_table);
+ }
+
+ if (ret == 0 && err)
+ ret = err;
+
+ for (i = 0; i < entries; i++) {
+ WARN(test_bit(i, obj_in_table), "elem %d allegedly still present", i);
+
+ err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node,
+ test_rht_params);
+ if (WARN(err, "error %d on element %d\n", err, i))
+ break;
+ if (err == 0)
+ set_bit(i, obj_in_table);
+ }
+
+ pr_info("test %d random rhlist add/delete operations\n", entries);
+ for (j = 0; j < entries; j++) {
+ u32 i = prandom_u32_max(entries);
+ u32 prand = prandom_u32();
+
+ cond_resched();
+
+ if (prand == 0)
+ prand = prandom_u32();
+
+ if (prand & 1) {
+ prand >>= 1;
+ continue;
+ }
+
+ err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+ if (test_bit(i, obj_in_table)) {
+ clear_bit(i, obj_in_table);
+ if (WARN(err, "cannot remove element at slot %d", i))
+ continue;
+ } else {
+ if (WARN(err != -ENOENT, "removed non-existent element %d, error %d not %d",
+ i, err, -ENOENT))
+ continue;
+ }
+
+ if (prand & 1) {
+ prand >>= 1;
+ continue;
+ }
+
+ err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+ if (err == 0) {
+ if (WARN(test_and_set_bit(i, obj_in_table), "succeeded to insert same object %d", i))
+ continue;
+ } else {
+ if (WARN(!test_bit(i, obj_in_table), "failed to insert object %d", i))
+ continue;
+ }
+
+ if (prand & 1) {
+ prand >>= 1;
+ continue;
+ }
+
+ i = prandom_u32_max(entries);
+ if (test_bit(i, obj_in_table)) {
+ err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+ WARN(err, "cannot remove element at slot %d", i);
+ if (err == 0)
+ clear_bit(i, obj_in_table);
+ } else {
+ err = rhltable_insert(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+ WARN(err, "failed to insert object %d", i);
+ if (err == 0)
+ set_bit(i, obj_in_table);
+ }
+ }
+
+ for (i = 0; i < entries; i++) {
+ cond_resched();
+ err = rhltable_remove(&rhlt, &rhl_test_objects[i].list_node, test_rht_params);
+ if (test_bit(i, obj_in_table)) {
+ if (WARN(err, "cannot remove element at slot %d", i))
+ continue;
+ } else {
+ if (WARN(err != -ENOENT, "removed non-existent element, error %d not %d",
+ err, -ENOENT))
+ continue;
+ }
+ }
+
+ rhltable_destroy(&rhlt);
+out_free:
+ vfree(rhl_test_objects);
+ vfree(obj_in_table);
+ return ret;
+}
+
+static int __init test_rhashtable_max(struct test_obj *array,
+ unsigned int entries)
+{
+ unsigned int i, insert_retries = 0;
+ int err;
+
+ test_rht_params.max_size = roundup_pow_of_two(entries / 8);
+ err = rhashtable_init(&ht, &test_rht_params);
+ if (err)
+ return err;
+
+ for (i = 0; i < ht.max_elems; i++) {
+ struct test_obj *obj = &array[i];
+
+ obj->value.id = i * 2;
+ err = insert_retry(&ht, obj, test_rht_params);
+ if (err > 0)
+ insert_retries += err;
+ else if (err)
+ return err;
+ }
+
+ err = insert_retry(&ht, &array[ht.max_elems], test_rht_params);
+ if (err == -E2BIG) {
+ err = 0;
+ } else {
+ pr_info("insert element %u should have failed with %d, got %d\n",
+ ht.max_elems, -E2BIG, err);
+ if (err == 0)
+ err = -1;
+ }
+
+ rhashtable_destroy(&ht);
+
+ return err;
+}
+
+static unsigned int __init print_ht(struct rhltable *rhlt)
+{
+ struct rhashtable *ht;
+ const struct bucket_table *tbl;
+ char buff[512] = "";
+ unsigned int i, cnt = 0;
+
+ ht = &rhlt->ht;
+ /* Take the mutex to avoid RCU warning */
+ mutex_lock(&ht->mutex);
+ tbl = rht_dereference(ht->tbl, ht);
+ for (i = 0; i < tbl->size; i++) {
+ struct rhash_head *pos, *next;
+ struct test_obj_rhl *p;
+
+ pos = rht_ptr_exclusive(tbl->buckets + i);
+ next = !rht_is_a_nulls(pos) ? rht_dereference(pos->next, ht) : NULL;
+
+ if (!rht_is_a_nulls(pos)) {
+ sprintf(buff, "%s\nbucket[%d] -> ", buff, i);
+ }
+
+ while (!rht_is_a_nulls(pos)) {
+ struct rhlist_head *list = container_of(pos, struct rhlist_head, rhead);
+ sprintf(buff, "%s[[", buff);
+ do {
+ pos = &list->rhead;
+ list = rht_dereference(list->next, ht);
+ p = rht_obj(ht, pos);
+
+ sprintf(buff, "%s val %d (tid=%d)%s", buff, p->value.id, p->value.tid,
+ list? ", " : " ");
+ cnt++;
+ } while (list);
+
+ pos = next,
+ next = !rht_is_a_nulls(pos) ?
+ rht_dereference(pos->next, ht) : NULL;
+
+ sprintf(buff, "%s]]%s", buff, !rht_is_a_nulls(pos) ? " -> " : "");
+ }
+ }
+ printk(KERN_ERR "\n---- ht: ----%s\n-------------\n", buff);
+ mutex_unlock(&ht->mutex);
+
+ return cnt;
+}
+
+static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
+ int cnt, bool slow)
+{
+ struct rhltable *rhlt;
+ unsigned int i, ret;
+ const char *key;
+ int err = 0;
+
+ rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
+ if (WARN_ON(!rhlt))
+ return -EINVAL;
+
+ err = rhltable_init(rhlt, &test_rht_params_dup);
+ if (WARN_ON(err)) {
+ kfree(rhlt);
+ return err;
+ }
+
+ for (i = 0; i < cnt; i++) {
+ rhl_test_objects[i].value.tid = i;
+ key = rht_obj(&rhlt->ht, &rhl_test_objects[i].list_node.rhead);
+ key += test_rht_params_dup.key_offset;
+
+ if (slow) {
+ err = PTR_ERR(rhashtable_insert_slow(&rhlt->ht, key,
+ &rhl_test_objects[i].list_node.rhead));
+ if (err == -EAGAIN)
+ err = 0;
+ } else
+ err = rhltable_insert(rhlt,
+ &rhl_test_objects[i].list_node,
+ test_rht_params_dup);
+ if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
+ goto skip_print;
+ }
+
+ ret = print_ht(rhlt);
+ WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
+
+skip_print:
+ rhltable_destroy(rhlt);
+ kfree(rhlt);
+
+ return 0;
+}
+
+static int __init test_insert_duplicates_run(void)
+{
+ struct test_obj_rhl rhl_test_objects[3] = {};
+
+ pr_info("test inserting duplicates\n");
+
+ /* two different values that map to same bucket */
+ rhl_test_objects[0].value.id = 1;
+ rhl_test_objects[1].value.id = 21;
+
+ /* and another duplicate with same as [0] value
+ * which will be second on the bucket list */
+ rhl_test_objects[2].value.id = rhl_test_objects[0].value.id;
+
+ test_insert_dup(rhl_test_objects, 2, false);
+ test_insert_dup(rhl_test_objects, 3, false);
+ test_insert_dup(rhl_test_objects, 2, true);
+ test_insert_dup(rhl_test_objects, 3, true);
+
+ return 0;
+}
+
+static int thread_lookup_test(struct thread_data *tdata)
+{
+ unsigned int entries = tdata->entries;
+ int i, err = 0;
+
+ for (i = 0; i < entries; i++) {
+ struct test_obj *obj;
+ struct test_obj_val key = {
+ .id = i,
+ .tid = tdata->id,
+ };
+
+ obj = rhashtable_lookup_fast(&ht, &key, test_rht_params);
+ if (obj && (tdata->objs[i].value.id == TEST_INSERT_FAIL)) {
+ pr_err(" found unexpected object %d-%d\n", key.tid, key.id);
+ err++;
+ } else if (!obj && (tdata->objs[i].value.id != TEST_INSERT_FAIL)) {
+ pr_err(" object %d-%d not found!\n", key.tid, key.id);
+ err++;
+ } else if (obj && memcmp(&obj->value, &key, sizeof(key))) {
+ pr_err(" wrong object returned (got %d-%d, expected %d-%d)\n",
+ obj->value.tid, obj->value.id, key.tid, key.id);
+ err++;
+ }
+
+ cond_resched();
+ }
+ return err;
+}
+
+static int threadfunc(void *data)
+{
+ int i, step, err = 0, insert_retries = 0;
+ struct thread_data *tdata = data;
+
+ if (atomic_dec_and_test(&startup_count))
+ wake_up(&startup_wait);
+ if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == -1)) {
+ pr_err(" thread[%d]: interrupted\n", tdata->id);
+ goto out;
+ }
+
+ for (i = 0; i < tdata->entries; i++) {
+ tdata->objs[i].value.id = i;
+ tdata->objs[i].value.tid = tdata->id;
+ err = insert_retry(&ht, &tdata->objs[i], test_rht_params);
+ if (err > 0) {
+ insert_retries += err;
+ } else if (err) {
+ pr_err(" thread[%d]: rhashtable_insert_fast failed\n",
+ tdata->id);
+ goto out;
+ }
+ }
+ if (insert_retries)
+ pr_info(" thread[%d]: %u insertions retried due to memory pressure\n",
+ tdata->id, insert_retries);
+
+ err = thread_lookup_test(tdata);
+ if (err) {
+ pr_err(" thread[%d]: rhashtable_lookup_test failed\n",
+ tdata->id);
+ goto out;
+ }
+
+ for (step = 10; step > 0; step--) {
+ for (i = 0; i < tdata->entries; i += step) {
+ if (tdata->objs[i].value.id == TEST_INSERT_FAIL)
+ continue;
+ err = rhashtable_remove_fast(&ht, &tdata->objs[i].node,
+ test_rht_params);
+ if (err) {
+ pr_err(" thread[%d]: rhashtable_remove_fast failed\n",
+ tdata->id);
+ goto out;
+ }
+ tdata->objs[i].value.id = TEST_INSERT_FAIL;
+
+ cond_resched();
+ }
+ err = thread_lookup_test(tdata);
+ if (err) {
+ pr_err(" thread[%d]: rhashtable_lookup_test (2) failed\n",
+ tdata->id);
+ goto out;
+ }
+ }
+out:
+ while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule();
+ }
+ return err;
+}
+
+static int __init test_rht_init(void)
+{
+ unsigned int entries;
+ int i, err, started_threads = 0, failed_threads = 0;
+ u64 total_time = 0;
+ struct thread_data *tdata;
+ struct test_obj *objs;
+
+ if (parm_entries < 0)
+ parm_entries = 1;
+
+ entries = min(parm_entries, MAX_ENTRIES);
+
+ test_rht_params.automatic_shrinking = shrinking;
+ test_rht_params.max_size = max_size ? : roundup_pow_of_two(entries);
+ test_rht_params.nelem_hint = size;
+
+ objs = vzalloc(array_size(sizeof(struct test_obj),
+ test_rht_params.max_size + 1));
+ if (!objs)
+ return -ENOMEM;
+
+ 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(objs, 0, test_rht_params.max_size * sizeof(struct test_obj));
+
+ 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, objs, entries);
+ rhashtable_destroy(&ht);
+ if (time < 0) {
+ vfree(objs);
+ pr_warn("Test failed: return code %lld\n", time);
+ return -EINVAL;
+ }
+
+ total_time += time;
+ }
+
+ pr_info("test if its possible to exceed max_size %d: %s\n",
+ test_rht_params.max_size, test_rhashtable_max(objs, entries) == 0 ?
+ "no, ok" : "YES, failed");
+ vfree(objs);
+
+ do_div(total_time, runs);
+ pr_info("Average test time: %llu\n", total_time);
+
+ test_insert_duplicates_run();
+
+ if (!tcount)
+ return 0;
+
+ pr_info("Testing concurrent rhashtable access from %d threads\n",
+ tcount);
+ atomic_set(&startup_count, tcount);
+ tdata = vzalloc(array_size(tcount, sizeof(struct thread_data)));
+ if (!tdata)
+ return -ENOMEM;
+ objs = vzalloc(array3_size(sizeof(struct test_obj), tcount, entries));
+ if (!objs) {
+ vfree(tdata);
+ return -ENOMEM;
+ }
+
+ test_rht_params.max_size = max_size ? :
+ roundup_pow_of_two(tcount * entries);
+ err = rhashtable_init(&ht, &test_rht_params);
+ if (err < 0) {
+ pr_warn("Test failed: Unable to initialize hashtable: %d\n",
+ err);
+ vfree(tdata);
+ vfree(objs);
+ return -EINVAL;
+ }
+ for (i = 0; i < tcount; i++) {
+ tdata[i].id = i;
+ tdata[i].entries = entries;
+ tdata[i].objs = objs + i * entries;
+ tdata[i].task = kthread_run(threadfunc, &tdata[i],
+ "rhashtable_thrad[%d]", i);
+ if (IS_ERR(tdata[i].task)) {
+ pr_err(" kthread_run failed for thread %d\n", i);
+ atomic_dec(&startup_count);
+ } else {
+ started_threads++;
+ }
+ }
+ if (wait_event_interruptible(startup_wait, atomic_read(&startup_count) == 0))
+ pr_err(" wait_event interruptible failed\n");
+ /* count is 0 now, set it to -1 and wake up all threads together */
+ atomic_dec(&startup_count);
+ wake_up_all(&startup_wait);
+ for (i = 0; i < tcount; i++) {
+ if (IS_ERR(tdata[i].task))
+ continue;
+ if ((err = kthread_stop(tdata[i].task))) {
+ pr_warn("Test failed: thread %d returned: %d\n",
+ i, err);
+ failed_threads++;
+ }
+ }
+ rhashtable_destroy(&ht);
+ vfree(tdata);
+ vfree(objs);
+
+ /*
+ * rhltable_remove is very expensive, default values can cause test
+ * to run for 2 minutes or more, use a smaller number instead.
+ */
+ err = test_rhltable(entries / 16);
+ pr_info("Started %d threads, %d failed, rhltable test returns %d\n",
+ started_threads, failed_threads, err);
+ return 0;
+}
+
+static void __exit test_rht_exit(void)
+{
+}
+
+module_init(test_rht_init);
+module_exit(test_rht_exit);
+
+MODULE_LICENSE("GPL v2");