一句话：提出 eHDL，从未修改的 eBPF/XDP 程序自动生成 FPGA NIC 硬件流水线。
网络包处理性能需利用设备硬件特性，但软件程序员需面对异构架构并重写软件。本文提出高层综合工具 eHDL，可将未修改的 Linux eBPF/XDP 程序自动转换为 NIC 硬件流水线，使无硬件经验的开发者也能定义有状态、作用于完整包数据的功能。作者在 Xilinx Alveo U50 FPGA NIC 上原型实现，用 5 个 eBPF/XDP 程序评估。生成流水线仅占 6.5%–13.3% FPGA 资源，转发达到线速且每包延迟约 1 微秒；相比基于处理器的 eBPF/XDP NIC 卸载方案，吞吐提高 10–100 倍。
Scaling network packet processing performance to meet the increasing speed of network ports requires software programs to carefully leverage the network devices’ hardware features. This is a complex task for network programmers, who need to learn and deal with the heterogeneity of device architectures, and re-think their software to leverage them. In this paper we make first steps to reverse this design process, enabling the automatic generation of tailored hardware designs starting from a network packet processing program. We introduce eHDL, a high-level synthesis tool that automatically generates hardware pipelines from unmodified Linux’s eBPF/XDP programs. eHDL is designed to enable software developers to directly define and implement the hardware functions they need in the NIC. We prototype eHDL targeting a Xilinx Alveo U50 FPGA NIC, and evaluate it with a set of 5 eBPF/XDP programs. Our results show that the generated pipelines are efficient in terms of required hardware resources, using only 6.5%-13.3% of the FPGA, and always achieve the line rate forwarding throughput with about 1 microsecond of per-packet forwarding latency. Compared to other network-specific high-level synthesis tool, eHDL enables software programmers with no hardware expertise to describe stateful functions that operate on the entire packet data. Compared to alternative processor-based solutions that perform eBFP/XDP offloading to a NIC, eHDL provides 10-100x higher throughput.
@inproceedings{paperbot10097,
title = {eHDL: Turning eBPF/XDP Programs into Hardware Designs for the NIC},
author = {Alessandro Rivitti and Roberto Bifulco and Angelo Tulumello and Marco Bonola and Salvatore Pontarelli},
booktitle = {ASPLOS},
year = {2023},
doi = {10.1145/3582016.3582035}
}