network/dctcp: add dctcp congestion control algorithm test

The test compares cubic and dctcp congestion control algorithms performance. One of the hosts emulates packets congestion with netem loss 0.03%. Also ECN is enabled on the host, which is required for dctcp algorithm to work properly.

Signed-off-by Alexey Kodanev <[email protected]>

---
  runtest/network_stress.features    |    3 +
  testcases/network/dctcp/Makefile   |   22 ++++++++
  testcases/network/dctcp/dctcp01.sh |  100 ++++++++++++++++++++++++++++++++++++
  3 files changed, 125 insertions(+), 0 deletions(-)

create mode 100644 testcases/network/dctcp/Makefile create mode 100755 testcases/network/dctcp/dctcp01.sh

runtest/network_stress.features +3 -0

index 668f3da..bb907e5 100644
@@ -31,3 +31,6 @@ ipvlan01 ipvlan01.sh
 
  gre_ipv4_01 gre01.sh
  gre_ipv6_01 gre01.sh -6
+
+dctcp_ipv4_01 dctcp01.sh
+dctcp_ipv6_01 dctcp01.sh -6

testcases/network/dctcp/Makefile new file +22 -0

new file mode 100644
index 0000000..82a6262
@@ -0,0 +1,22 @@
+# Copyright (c) 2015 Oracle and/or its affiliates. All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+top_srcdir		?= ../../..
+
+include $(top_srcdir)/include/mk/env_pre.mk
+
+INSTALL_TARGETS		:= dctcp01.sh
+
+include $(top_srcdir)/include/mk/generic_leaf_target.mk

testcases/network/dctcp/dctcp01.sh new file +100 -0

new file mode 100755
index 0000000..7181abc
@@ -0,0 +1,100 @@
+#!/bin/sh
+# Copyright (c) 2015 Oracle and/or its affiliates. All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+# Author: Alexey Kodanev <[email protected]>
+
+TCID=dctcp01
+TST_TOTAL=1
+TST_CLEANUP="cleanup"
+def_alg="cubic"
+prev_alg=
+
+. test_net.sh
+
+set_cong_alg()
+{
+	local alg=$1
+	tst_resm TINFO "setting $alg"
+
+	ROD sysctl -q -w net.ipv4.tcp_congestion_control=$alg
+	tst_rhost_run -s -c "sysctl -q -w net.ipv4.tcp_congestion_control=$alg"
+}
+
+cleanup()
+{
+	if [ "$prev_cong_ctl" ]; then
+		sysctl -q -w net.ipv4.tcp_congestion_control=$prev_alg
+		tst_rhost_run -c \
+			"sysctl -q -w net.ipv4.tcp_congestion_control=$prev_alg"
+	fi
+	tst_rmdir
+	tc qdisc del dev $(tst_iface) root netem loss 0.03% ecn
+}
+
+setup()
+{
+	tst_require_root
+	tst_check_cmds ip sysctl tc
+
+	tst_resm TINFO "emulate congestion with packet loss 0.03% and ECN"
+	tc qdisc add dev $(tst_iface) root netem loss 0.03% ecn > /dev/null 2>&1
+	if [ $? -ne 0 ]; then
+		tst_brkm TCONF "netem doesn't support ECN"
+	fi
+
+	tst_tmpdir
+
+	prev_alg="$(cat /proc/sys/net/ipv4/tcp_congestion_control)"
+}
+
+test_run()
+{
+	tst_resm TINFO "compare '$def_alg' and 'dctcp' congestion alg. results"
+
+	set_cong_alg "$def_alg"
+
+	tst_netload $(tst_ipaddr rhost) tfo_res TFO
+	if [ $? -ne 0 ]; then
+		tst_resm TFAIL "test with '$def_alg' has failed"
+		return
+	fi
+	local res0="$(cat tfo_res)"
+	tst_resm TINFO "$def_alg time '$res0' ms"
+
+	set_cong_alg "dctcp"
+
+	tst_netload $(tst_ipaddr rhost) tfo_res TFO
+	if [ $? -ne 0 ]; then
+		tst_resm TFAIL "test with 'dctcp' has failed"
+		return
+	fi
+	local res1="$(cat tfo_res)"
+	tst_resm TINFO "dctcp time '$res1' ms"
+
+	local per=$(( $res0 * 100 / $res1 - 100 ))
+
+	if [ "$per" -lt "10" ]; then
+		tst_resm TFAIL "dctcp performance $per %"
+	else
+		tst_resm TPASS "dctcp performance $per %"
+	fi
+}
+
+setup
+
+test_run
+
+tst_exit