l += vlib_buffer_index_length_in_chain (vm, buffers[i]);
vlib_increment_combined_counter (im->combined_sw_if_counters
+ VNET_INTERFACE_COUNTER_RX,
l += vlib_buffer_index_length_in_chain (vm, buffers[i]);
vlib_increment_combined_counter (im->combined_sw_if_counters
+ VNET_INTERFACE_COUNTER_RX,