tools/testing/selftests/bpf/test_tc_edt.sh

   1 #!/bin/bash
   2 # SPDX-License-Identifier: GPL-2.0
   3 #
   4 # This test installs a TC bpf program that throttles a TCP flow
   5 # with dst port = 9000 down to 5MBps. Then it measures actual
   6 # throughput of the flow.
   7
   8 if [[ $EUID -ne 0 ]]; then
   9         echo "This script must be run as root"
  10         echo "FAIL"
  11         exit 1
  12 fi
  13
  14 # check that nc, dd, and timeout are present
  15 command -v nc >/dev/null 2>&1 || \
  16         { echo >&2 "nc is not available"; exit 1; }
  17 command -v dd >/dev/null 2>&1 || \
  18         { echo >&2 "nc is not available"; exit 1; }
  19 command -v timeout >/dev/null 2>&1 || \
  20         { echo >&2 "timeout is not available"; exit 1; }
  21
  22 readonly NS_SRC="ns-src-$(mktemp -u XXXXXX)"
  23 readonly NS_DST="ns-dst-$(mktemp -u XXXXXX)"
  24
  25 readonly IP_SRC="172.16.1.100"
  26 readonly IP_DST="172.16.2.100"
  27
  28 cleanup()
  29 {
  30         ip netns del ${NS_SRC}
  31         ip netns del ${NS_DST}
  32 }
  33
  34 trap cleanup EXIT
  35
  36 set -e  # exit on error
  37
  38 ip netns add "${NS_SRC}"
  39 ip netns add "${NS_DST}"
  40 ip link add veth_src type veth peer name veth_dst
  41 ip link set veth_src netns ${NS_SRC}
  42 ip link set veth_dst netns ${NS_DST}
  43
  44 ip -netns ${NS_SRC} addr add ${IP_SRC}/24  dev veth_src
  45 ip -netns ${NS_DST} addr add ${IP_DST}/24  dev veth_dst
  46
  47 ip -netns ${NS_SRC} link set dev veth_src up
  48 ip -netns ${NS_DST} link set dev veth_dst up
  49
  50 ip -netns ${NS_SRC} route add ${IP_DST}/32  dev veth_src
  51 ip -netns ${NS_DST} route add ${IP_SRC}/32  dev veth_dst
  52
  53 # set up TC on TX
  54 ip netns exec ${NS_SRC} tc qdisc add dev veth_src root fq
  55 ip netns exec ${NS_SRC} tc qdisc add dev veth_src clsact
  56 ip netns exec ${NS_SRC} tc filter add dev veth_src egress \
  57         bpf da obj test_tc_edt.o sec cls_test
  58
  59
  60 # start the listener
  61 ip netns exec ${NS_DST} bash -c \
  62         "nc -4 -l -p 9000 >/dev/null &"
  63 declare -i NC_PID=$!
  64 sleep 1
  65
  66 declare -ir TIMEOUT=20
  67 declare -ir EXPECTED_BPS=5000000
  68
  69 # run the load, capture RX bytes on DST
  70 declare -ir RX_BYTES_START=$( ip netns exec ${NS_DST} \
  71         cat /sys/class/net/veth_dst/statistics/rx_bytes )
  72
  73 set +e
  74 ip netns exec ${NS_SRC} bash -c "timeout ${TIMEOUT} dd if=/dev/zero \
  75         bs=1000 count=1000000 > /dev/tcp/${IP_DST}/9000 2>/dev/null"
  76 set -e
  77
  78 declare -ir RX_BYTES_END=$( ip netns exec ${NS_DST} \
  79         cat /sys/class/net/veth_dst/statistics/rx_bytes )
  80
  81 declare -ir ACTUAL_BPS=$(( ($RX_BYTES_END - $RX_BYTES_START) / $TIMEOUT ))
  82
  83 echo $TIMEOUT $ACTUAL_BPS $EXPECTED_BPS | \
  84         awk '{printf "elapsed: %d sec; bps difference: %.2f%%\n",
  85                 $1, ($2-$3)*100.0/$3}'
  86
  87 # Pass the test if the actual bps is within 1% of the expected bps.
  88 # The difference is usually about 0.1% on a 20-sec test, and ==> zero
  89 # the longer the test runs.
  90 declare -ir RES=$( echo $ACTUAL_BPS $EXPECTED_BPS | \
  91          awk 'function abs(x){return ((x < 0.0) ? -x : x)}
  92               {if (abs(($1-$2)*100.0/$2) > 1.0) { print "1" }
  93                 else { print "0"} }' )
  94 if [ "${RES}" == "0" ] ; then
  95         echo "PASS"
  96 else
  97         echo "FAIL"
  98         exit 1
  99 fi