+#define MLX5_FLOW_MIN_ID_POOL_SIZE 512
+#define MLX5_ID_GENERATION_ARRAY_FACTOR 16
+
+/**
+ * Allocate ID pool structure.
+ *
+ * @return
+ * Pointer to pool object, NULL value otherwise.
+ */
+struct mlx5_flow_id_pool *
+mlx5_flow_id_pool_alloc(void)
+{
+ struct mlx5_flow_id_pool *pool;
+ void *mem;
+
+ pool = rte_zmalloc("id pool allocation", sizeof(*pool),
+ RTE_CACHE_LINE_SIZE);
+ if (!pool) {
+ DRV_LOG(ERR, "can't allocate id pool");
+ rte_errno = ENOMEM;
+ return NULL;
+ }
+ mem = rte_zmalloc("", MLX5_FLOW_MIN_ID_POOL_SIZE * sizeof(uint32_t),
+ RTE_CACHE_LINE_SIZE);
+ if (!mem) {
+ DRV_LOG(ERR, "can't allocate mem for id pool");
+ rte_errno = ENOMEM;
+ goto error;
+ }
+ pool->free_arr = mem;
+ pool->curr = pool->free_arr;
+ pool->last = pool->free_arr + MLX5_FLOW_MIN_ID_POOL_SIZE;
+ pool->base_index = 0;
+ return pool;
+error:
+ rte_free(pool);
+ return NULL;
+}
+
+/**
+ * Release ID pool structure.
+ *
+ * @param[in] pool
+ * Pointer to flow id pool object to free.
+ */
+void
+mlx5_flow_id_pool_release(struct mlx5_flow_id_pool *pool)
+{
+ rte_free(pool->free_arr);
+ rte_free(pool);
+}
+
+/**
+ * Generate ID.
+ *
+ * @param[in] pool
+ * Pointer to flow id pool.
+ * @param[out] id
+ * The generated ID.
+ *
+ * @return
+ * 0 on success, error value otherwise.
+ */
+uint32_t
+mlx5_flow_id_get(struct mlx5_flow_id_pool *pool, uint32_t *id)
+{
+ if (pool->curr == pool->free_arr) {
+ if (pool->base_index == UINT32_MAX) {
+ rte_errno = ENOMEM;
+ DRV_LOG(ERR, "no free id");
+ return -rte_errno;
+ }
+ *id = ++pool->base_index;
+ return 0;
+ }
+ *id = *(--pool->curr);
+ return 0;
+}
+
+/**
+ * Release ID.
+ *
+ * @param[in] pool
+ * Pointer to flow id pool.
+ * @param[out] id
+ * The generated ID.
+ *
+ * @return
+ * 0 on success, error value otherwise.
+ */
+uint32_t
+mlx5_flow_id_release(struct mlx5_flow_id_pool *pool, uint32_t id)
+{
+ uint32_t size;
+ uint32_t size2;
+ void *mem;
+
+ if (pool->curr == pool->last) {
+ size = pool->curr - pool->free_arr;
+ size2 = size * MLX5_ID_GENERATION_ARRAY_FACTOR;
+ assert(size2 > size);
+ mem = rte_malloc("", size2 * sizeof(uint32_t), 0);
+ if (!mem) {
+ DRV_LOG(ERR, "can't allocate mem for id pool");
+ rte_errno = ENOMEM;
+ return -rte_errno;
+ }
+ memcpy(mem, pool->free_arr, size * sizeof(uint32_t));
+ rte_free(pool->free_arr);
+ pool->free_arr = mem;
+ pool->curr = pool->free_arr + size;
+ pool->last = pool->free_arr + size2;
+ }
+ *pool->curr = id;
+ pool->curr++;
+ return 0;
+}
+