Cyborg FPGA Programming Service Proposal¶

Problem description¶

A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturing. Their advantage lies in that they are sometimes significantly faster for some applications because of their parallel nature and optimality in terms of the number of gates used for a certain process. In addition, FPGA can be reprogrammed based on different applications Hence, using FPGA for application acceleration in cloud has been becoming desirable. Cyborg as a management framwork for heterogeneous accelerators, tracking, deploying and reprogramming FPGAs are much needed features. Since the FPGA modelling has already been proposed in another document, this spec will be focused on proposing Reporgramming Service for FPGAs in Cyborg

Proposed change¶

First of all, Cyborg needs to add extra REST APIs to allow others to invoke the programming service. The REST api should have following format:

Url: {base_url}/fpga/{deployable_uuid}
Method: POST
URL Params:
    None

Data Params:
    glance_bitstream_uuid

Success Response:
    POST:
        Code: 200
        Body: { "msg" : "bitstream has been loaded successfully"}

Error Response
    Code: 401 UNAUTHORIZED
    Body: { error : "Log in" }
    OR
    Code: 422 Unprocessable Entry
    Body: { error : "User is not authorized to use the resource" }

Sample Call:
    To program fpga resource with deployable_uuid=2864a139-c2cd-4f9f-abf3-44eb3f09b83c
    with bitstream with uuid=0b955a5b-f5dd-49d0-8c4f-28729427d303
    $.ajax({
      url: "/fpga/2864a139-c2cd-4f9f-abf3-44eb3f09b83c",
      data: {
        "glance_bitstream_uuid": "0b955a5b-f5dd-49d0-8c4f-28729427d303"
      },
      dataType: "json",
      type : "post",
      success : function(r) {
        console.log(r);
      }
    });

Second, implement the service in Cyborg which does three tasks: 1. identify the host location of the requested FPGA/Partial Reconfiguraion(PR) Region(e.g. on which host is the board located). 2. Check if the user(API caller, OpenStack Login User, etc) has the privilige to use the given bitstream, FPGA, or host. 3. If the previous checks pass, Cyborg will send the program notification to the target host with requested FPGA.

Third, implement notification callee in Cyborg Agent. This should be a rpc call with following signature:

int program_fpga_with_bitstream(deployable_uuid, bitstream_uuid)

The function takes both deployable_uuid and bitstream_uuid as input. It uses deployable_uuid to identify which specific FPGA/PR region is going to be programmed and uses bitstream_uuid to retrieve bitstream from the bitstream storage service (Glance in the context of OpenStack). In addition, this is a synchronous meaning it will wait for the programming task to be completed and then return a status code as integer. The return code should have following interpretation:

Implementation¶

Dependencies¶

Testing¶

Documentation Impact¶

The Cyborg-Nova interaction related specs need to be aware the change of the accelerators when FPGAs are being reprogrammed.

References¶

None

History¶