if(~0 == mask_type_index) {
pool_get_aligned (am->ace_mask_type_pool, mte, CLIB_CACHE_LINE_BYTES);
mask_type_index = mte - am->ace_mask_type_pool;
if(~0 == mask_type_index) {
pool_get_aligned (am->ace_mask_type_pool, mte, CLIB_CACHE_LINE_BYTES);
mask_type_index = mte - am->ace_mask_type_pool;