[PATCH v6 7/7] test/hash: add test for key compare functions

Stephen Hemminger
2026-03-29T23:25:00Z

The hash library has optimized key compare functions for various
key lengths (in rte_cmp_jump_table). Add a test that creates hash
tables with each length in hashtest_key_lens[] and verifies that
add, lookup, and delete work correctly. The test also verifies
that the compare function properly detects when a key differs
by modifying the last byte and confirming lookup fails.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
app/test/test_hash.c | 78 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 78 insertions(+)

diff --git a/app/test/test_hash.c b/app/test/test_hash.c
index 0ddf71ff3c..640a33e16c 100644
--- a/app/test/test_hash.c
+++ b/app/test/test_hash.c
@@ -1515,6 +1515,83 @@ test_hash_creation_with_good_parameters(void)
return 0;
}

+/*
+ * Test hash creation and key operations with various key lengths.
+ * This exercises the key compare functions for different sizes.
+ */
+static int
+test_hash_creation_with_key_lengths(void)
+{
+ struct rte_hash *handle;
+ struct rte_hash_parameters params;
+ uint8_t key[MAX_KEYSIZE];
+ unsigned int i, j;
+ int pos, expected_pos;
+
+ for (i = 0; i < RTE_DIM(hashtest_key_lens); i++) {
+ uint32_t key_len = hashtest_key_lens[i];
+
+ /* key_len of 0 is invalid */
+ if (key_len == 0)
+ continue;
+
+ memcpy(&params, &ut_params, sizeof(params));
+ params.name = "key_len_test";
+ params.key_len = key_len;
+
+ handle = rte_hash_create(&params);
+ if (handle == NULL) {
+ printf("Creating hash with key_len %u failed\n", key_len);
+ return -1;
+ }
+
+ /* initialize key with pattern */
+ for (j = 0; j < key_len; j++)
+ key[j] = (uint8_t)j;
+
+ /* add the key */
+ pos = rte_hash_add_key(handle, key);
+ if (pos < 0) {
+ printf("Adding key with key_len %u failed\n", key_len);
+ rte_hash_free(handle);
+ return -1;
+ }
+ expected_pos = pos;
+
+ /* lookup should find same key */
+ pos = rte_hash_lookup(handle, key);
+ if (pos != expected_pos) {
+ printf("Lookup key with key_len %u failed: expected %d got %d\n",
+ key_len, expected_pos, pos);
+ rte_hash_free(handle);
+ return -1;
+ }
+
+ /* modify one byte and lookup should fail */
+ key[key_len - 1] ^= 0xff;
+ pos = rte_hash_lookup(handle, key);
+ if (pos != -ENOENT) {
+ printf("Lookup modified key with key_len %u should have failed\n",
+ key_len);
+ rte_hash_free(handle);
+ return -1;
+ }
+
+ /* restore key and delete */
+ key[key_len - 1] ^= 0xff;
+ pos = rte_hash_del_key(handle, key);
+ if (pos != expected_pos) {
+ printf("Delete key with key_len %u failed\n", key_len);
+ rte_hash_free(handle);
+ return -1;
+ }
+
+ rte_hash_free(handle);
+ }
+
+ return 0;
+}
+
#define ITERATIONS 3
/*
* Test to see the average table utilization (entries added/max entries)
@@ -2563,6 +2640,7 @@ static struct unit_test_suite hash_test_suite = {
TEST_CASE(fbk_hash_unit_test),
TEST_CASE(test_hash_creation_with_bad_parameters),
TEST_CASE(test_hash_creation_with_good_parameters),
+ TEST_CASE(test_hash_creation_with_key_lengths),
TEST_CASE(test_average_table_utilization_no_ext),
TEST_CASE(test_hash_iteration_no_ext),
TEST_CASE(test_average_table_utilization_ext),
--
2.53.0