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
111