[dpdk-dev] [PATCH v4] lib/table: fix cache alignment issue

[Ting Xu]

When create softnic hash table with 16 keys, it failed on 32-bit
environment, because the pointer field in structure rte_bucket_4_16
is only 32 bits. Add a padding field in 32-bit environment to keep
the structure to a multiple of 64 bytes. Apply this to 8-byte and
32-byte key hash function as well.

Fixes: 8aa327214c ("table: hash")
Cc: stable at dpdk.org

Signed-off-by: Ting Xu <ting.xu at intel.com>

---
v3->v4: Change design based on comment
v2->v3: Rebase
v1->v2: Correct patch time
---
 lib/librte_table/rte_table_hash_key16.c | 17 +++++++++++++++++
 lib/librte_table/rte_table_hash_key32.c | 17 +++++++++++++++++
 lib/librte_table/rte_table_hash_key8.c  | 16 ++++++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/lib/librte_table/rte_table_hash_key16.c b/lib/librte_table/rte_table_hash_key16.c
index 2cca1c924..c4384b114 100644
--- a/lib/librte_table/rte_table_hash_key16.c
+++ b/lib/librte_table/rte_table_hash_key16.c
@@ -33,6 +33,7 @@
 
 #endif
 
+#ifdef RTE_ARCH_64
 struct rte_bucket_4_16 {
 	/* Cache line 0 */
 	uint64_t signature[4 + 1];
@@ -46,6 +47,22 @@ struct rte_bucket_4_16 {
 	/* Cache line 2 */
 	uint8_t data[0];
 };
+#else
+struct rte_bucket_4_16 {
+	/* Cache line 0 */
+	uint64_t signature[4 + 1];
+	uint64_t lru_list;
+	struct rte_bucket_4_16 *next;
+	uint32_t pad;
+	uint64_t next_valid;
+
+	/* Cache line 1 */
+	uint64_t key[4][2];
+
+	/* Cache line 2 */
+	uint8_t data[0];
+};
+#endif
 
 struct rte_table_hash {
 	struct rte_table_stats stats;
diff --git a/lib/librte_table/rte_table_hash_key32.c b/lib/librte_table/rte_table_hash_key32.c
index a137c5028..3e0031fe1 100644
--- a/lib/librte_table/rte_table_hash_key32.c
+++ b/lib/librte_table/rte_table_hash_key32.c
@@ -33,6 +33,7 @@
 
 #endif
 
+#ifdef RTE_ARCH_64
 struct rte_bucket_4_32 {
 	/* Cache line 0 */
 	uint64_t signature[4 + 1];
@@ -46,6 +47,22 @@ struct rte_bucket_4_32 {
 	/* Cache line 3 */
 	uint8_t data[0];
 };
+#else
+struct rte_bucket_4_32 {
+	/* Cache line 0 */
+	uint64_t signature[4 + 1];
+	uint64_t lru_list;
+	struct rte_bucket_4_32 *next;
+	uint32_t pad;
+	uint64_t next_valid;
+
+	/* Cache lines 1 and 2 */
+	uint64_t key[4][4];
+
+	/* Cache line 3 */
+	uint8_t data[0];
+};
+#endif
 
 struct rte_table_hash {
 	struct rte_table_stats stats;
diff --git a/lib/librte_table/rte_table_hash_key8.c b/lib/librte_table/rte_table_hash_key8.c
index 1811ad8d0..34e3ed1af 100644
--- a/lib/librte_table/rte_table_hash_key8.c
+++ b/lib/librte_table/rte_table_hash_key8.c
@@ -31,6 +31,7 @@
 
 #endif
 
+#ifdef RTE_ARCH_64
 struct rte_bucket_4_8 {
 	/* Cache line 0 */
 	uint64_t signature;
@@ -43,6 +44,21 @@ struct rte_bucket_4_8 {
 	/* Cache line 1 */
 	uint8_t data[0];
 };
+#else
+struct rte_bucket_4_8 {
+	/* Cache line 0 */
+	uint64_t signature;
+	uint64_t lru_list;
+	struct rte_bucket_4_8 *next;
+	uint32_t pad;
+	uint64_t next_valid;
+
+	uint64_t key[4];
+
+	/* Cache line 1 */
+	uint8_t data[0];
+};
+#endif
 
 struct rte_table_hash {
 	struct rte_table_stats stats;
-- 
2.17.1