A MoonGen script: tx udp packets

tx-udp.lua

-- This test does the following:
--	2. Send UDP packets from NIC 1 to NIC 2
--

local mg     = require "moongen"
local memory = require "memory"
local device = require "device"
local ts     = require "timestamping"
local filter = require "filter"
local hist   = require "histogram"
local stats  = require "stats"
local timer  = require "timer"
local arp    = require "proto.arp"
local log    = require "log"
local timer  = require "timer"

local ffi = require "ffi"

-- set addresses here
local SRC_MAC     = "ec:0d:9a:7d:84:4e"
local DST_MAC     = "ec:0d:9a:7d:83:06"
local SRC_IP_BASE = "10.0.0.2"
local DST_IP      = "10.0.0.1"
local SRC_PORT    = 1234
local DST_PORT    = 60000



local C = ffi.C

function configure(parser)
	parser:description("Generates UDP traffic.")
	parser:argument("txDev", "Device to transmit from."):convert(tonumber)
	parser:option("-q --qnum", "Queue num to be used for TX"):default(1):convert(tonumber)
	parser:option("-s --size", "Packet size."):default(60):convert(tonumber)
	parser:option("-t --timeout", "timeout"):default(0):convert(tonumber)
end


function master(args)
	txDev = device.config{port = args.txDev, txQueues = args.qnum}
	device.waitForLinks()

	for n = 0, args.qnum - 1 do
		mg.startTask("loadSlave", txDev:getTxQueue(n), args.size, args.timeout)
	end
	mg.waitForTasks()
end


local function fillUdpPacket(buf, len)
	buf:getUdpPacket():fill{
		ethSrc = SRC_MAC,
		ethDst = DST_MAC,
		ip4Src = SRC_IP,
		ip4Dst = DST_IP,
		udpSrc = SRC_PORT,
		udpDst = DST_PORT,
		pktLength = len
	}
end


--- Runs on the sending NIC
--- Generates UDP traffic and also fetches the stats
function loadSlave(queue, size, timeout)

	log:info(green("Starting up: LoadSlave"))

	local timer = timer:new(timeout)

	local mempool = memory.createMemPool(function(buf)
		fillUdpPacket(buf, size)
	end)
	local bufs = mempool:bufArray()
	local txCtr = stats:newDevTxCounter(queue, "plain")
	local baseIP = parseIPAddress(SRC_IP_BASE)


	-- send out UDP packets until the user stops the script
	while mg.running() do
		bufs:alloc(size)
		for i, buf in ipairs(bufs) do
			local pkt = buf:getUdpPacket()
			pkt.ip4.src:set(baseIP)
			pkt.udp.src = i + 1234
		end
		--- UDP checksums are optional, so using just IPv4 checksums would be sufficient here
		bufs:offloadUdpChecksums()
		queue:send(bufs)
		txCtr:update()

		if timeout > 0 and timer:expired() then
			break
		end
	end
	txCtr:finalize()

end