[net-next v2 3/4] test_rhashtable: add a check for max_size

[Florian Westphal]

add a test that tries to insert more than max_size elements.

Signed-off-by: Florian Westphal <f...@strlen.de>
---
 lib/test_rhashtable.c | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c
index 69f5b3849980..1eee90e6e394 100644
--- a/lib/test_rhashtable.c
+++ b/lib/test_rhashtable.c
@@ -246,6 +246,43 @@ static s64 __init test_rhashtable(struct rhashtable *ht, 
struct test_obj *array,
 
 static struct rhashtable ht;
 
+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 int thread_lookup_test(struct thread_data *tdata)
 {
        unsigned int entries = tdata->entries;
@@ -386,7 +423,11 @@ static int __init test_rht_init(void)
                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);
 
-- 
2.13.5