Using Plugin Techniques for Programmable IO Devices

1
Using Plug-in Techniques for Programmable I/O
Devices

• Cheng Liao
• Margaret Martonosi
• Douglas W. Clark

2
Motivation

• Fast spread of programmable I/O devices
• Work assignment between main processor and
  co-processor on devices
• Different higher layers often require specialized
  low-level support
• Users need to access low-level information
• Separation of low-level high-level developers
• Low-level programming is hard

3
Plug-in Approach Overview

• Base implementation only includes absolutely
  necessary functionality
• Base implementation exports accessing points for
  user-defined plug-ins
• User can dynamically load user-specific code into
  the firmware
• Programming-model specific plug-ins
• Application specific plug-ins

4
VMMC Overview
5
VMMC Firmware on Myrinet NI
6
Plug-in Approach Implementation

• Program-model identifier application identifier
  are assigned
• Different plug-ins for different
  programming-model / application can coexist
• Default plug-ins

7
Overhead of Plug-ins in Firmware
8
Possible Usage

• Redirection (0-copy) for MPI, etc.
• Multicast
• Scatter and gather
• User-tailored performance tool
• User-tailored debugging tool

9
Security Issues

• Use compiler to enforce security
• Restricted C
• Loop transformation
• Compiler-approved signature
• Plug-in loader checks the compiler-approved
  signature when load plug-ins into firmware