1#!/bin/bash
  2# SPDX-License-Identifier: GPL-2.0
  3#
  4# Script for max single flow performance
  5#  - If correctly tuned[1], single CPU 10G wirespeed small pkts is possible[2]
  6#
  7# Using pktgen "burst" option (use -b $N)
  8#  - To boost max performance
  9#  - Avail since: kernel v3.18
 10#   * commit 38b2cf2982dc73 ("net: pktgen: packet bursting via skb->xmit_more")
 11#  - This avoids writing the HW tailptr on every driver xmit
 12#  - The performance boost is impressive, see commit and blog [2]
 13#
 14# Notice: On purpose generates a single (UDP) flow towards target,
 15#   reason behind this is to only overload/activate a single CPU on
 16#   target host.  And no randomness for pktgen also makes it faster.
 17#
 18# Tuning see:
 19#  [1] http://netoptimizer.blogspot.dk/2014/06/pktgen-for-network-overload-testing.html
 20#  [2] http://netoptimizer.blogspot.dk/2014/10/unlocked-10gbps-tx-wirespeed-smallest.html
 21#
 22basedir=`dirname $0`
 23source ${basedir}/functions.sh
 24root_check_run_with_sudo "$@"
 25
 26# Parameter parsing via include
 27source ${basedir}/parameters.sh
 28
 29# Trap EXIT first
 30trap_exit
 31
 32# Set some default params, if they didn't get set
 33if [ -z "$DEST_IP" ]; then
 34    [ -z "$IP6" ] && DEST_IP="198.18.0.42" || DEST_IP="FD00::1"
 35fi
 36[ -z "$DST_MAC" ]   && DST_MAC="90:e2:ba:ff:ff:ff"
 37[ -z "$BURST" ]     && BURST=32
 38[ -z "$CLONE_SKB" ] && CLONE_SKB="0" # No need for clones when bursting
 39[ -z "$COUNT" ]     && COUNT="0" # Zero means indefinitely
 40if [ -n "$DEST_IP" ]; then
 41    validate_addr${IP6} $DEST_IP
 42    read -r DST_MIN DST_MAX <<< $(parse_addr${IP6} $DEST_IP)
 43fi
 44if [ -n "$DST_PORT" ]; then
 45    read -r UDP_DST_MIN UDP_DST_MAX <<< $(parse_ports $DST_PORT)
 46    validate_ports $UDP_DST_MIN $UDP_DST_MAX
 47fi
 48
 49# General cleanup everything since last run
 50[ -z "$APPEND" ] && pg_ctrl "reset"
 51
 52# Threads are specified with parameter -t value in $THREADS
 53for ((thread = $F_THREAD; thread <= $L_THREAD; thread++)); do
 54    dev=${DEV}@${thread}
 55
 56    # Add remove all other devices and add_device $dev to thread
 57    [ -z "$APPEND" ] && pg_thread $thread "rem_device_all"
 58    pg_thread $thread "add_device" $dev
 59
 60    # Base config
 61    pg_set $dev "flag QUEUE_MAP_CPU"
 62    pg_set $dev "count $COUNT"
 63    pg_set $dev "clone_skb $CLONE_SKB"
 64    pg_set $dev "pkt_size $PKT_SIZE"
 65    pg_set $dev "delay $DELAY"
 66    pg_set $dev "flag NO_TIMESTAMP"
 67
 68    # Destination
 69    pg_set $dev "dst_mac $DST_MAC"
 70    pg_set $dev "dst${IP6}_min $DST_MIN"
 71    pg_set $dev "dst${IP6}_max $DST_MAX"
 72
 73    if [ -n "$DST_PORT" ]; then
 74	# Single destination port or random port range
 75	pg_set $dev "flag UDPDST_RND"
 76	pg_set $dev "udp_dst_min $UDP_DST_MIN"
 77	pg_set $dev "udp_dst_max $UDP_DST_MAX"
 78    fi
 79
 80    [ ! -z "$UDP_CSUM" ] && pg_set $dev "flag UDPCSUM"
 81
 82    # Setup burst, for easy testing -b 0 disable bursting
 83    # (internally in pktgen default and minimum burst=1)
 84    if [[ ${BURST} -ne 0 ]]; then
 85	pg_set $dev "burst $BURST"
 86    else
 87	info "$dev: Not using burst"
 88    fi
 89done
 90
 91# Run if user hits control-c
 92function print_result() {
 93    # Print results
 94    for ((thread = $F_THREAD; thread <= $L_THREAD; thread++)); do
 95	dev=${DEV}@${thread}
 96	echo "Device: $dev"
 97	cat /proc/net/pktgen/$dev | grep -A2 "Result:"
 98    done
 99}
100# trap keyboard interrupt (Ctrl-C)
101trap true SIGINT
102
103if [ -z "$APPEND" ]; then
104    echo "Running... ctrl^C to stop" >&2
105    pg_ctrl "start"
106
107    print_result
108else
109    echo "Append mode: config done. Do more or use 'pg_ctrl start' to run"
110fi