selftests: mptcp: add option to specify size of file to transfer

The script generates two random files that are then sent via tcp and
mptcp connections.

In order to compare throughput over consecutive runs add an option
to provide the file size on the command line: "-f 128000".

Also add an option, -t, to enable tcp tests. This is useful to
compare throughput of mptcp connections and tcp connections.

Example: run tests with a 4mb file size, 300ms delay 0.01% loss,
default gso/tso/gro settings and with large write/blocking io:

mptcp_connect.sh -t -f $((4 * 1024 * 1024)) -d 300 -l 0.01%  -r 0 -e "" -m mmap
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/mptcp/mptcp_connect.sh

@@ -3,7 +3,7 @@
 
 time_start=$(date +%s)
 
-optstring="S:R:d:e:l:r:h4cm:"
+optstring="S:R:d:e:l:r:h4cm:f:t"
 ret=0
 sin=""
 sout=""
@@ -21,6 +21,8 @@ testmode=""
 sndbuf=0
 rcvbuf=0
 options_log=true
+do_tcp=0
+filesize=0
 
 if [ $tc_loss -eq 100 ];then
 	tc_loss=1%
@@ -40,9 +42,11 @@ usage() {
 	echo -e "\t-e: ethtool features to disable, e.g.: \"-e tso -e gso\" (default: randomly disable any of tso/gso/gro)"
 	echo -e "\t-4: IPv4 only: disable IPv6 tests (default: test both IPv4 and IPv6)"
 	echo -e "\t-c: capture packets for each test using tcpdump (default: no capture)"
+	echo -e "\t-f: size of file to transfer in bytes (default random)"
 	echo -e "\t-S: set sndbuf value (default: use kernel default)"
 	echo -e "\t-R: set rcvbuf value (default: use kernel default)"
 	echo -e "\t-m: test mode (poll, sendfile; default: poll)"
+	echo -e "\t-t: also run tests with TCP (use twice to non-fallback tcp)"
 }
 
 while getopts "$optstring" option;do
@@ -94,6 +98,12 @@ while getopts "$optstring" option;do
 	"m")
 		testmode="$OPTARG"
 		;;
+	"f")
+		filesize="$OPTARG"
+		;;
+	"t")
+		do_tcp=$((do_tcp+1))
+		;;
 	"?")
 		usage $0
 		exit 1
@@ -449,20 +459,25 @@ make_file()
 {
 	local name=$1
 	local who=$2
+	local SIZE=$filesize
+	local ksize
+	local rem
+
+	if [ $SIZE -eq 0 ]; then
+		local MAXSIZE=$((1024 * 1024 * 8))
+		local MINSIZE=$((1024 * 256))
 
-	local SIZE TSIZE
-	SIZE=$((RANDOM % (1024 * 8)))
-	TSIZE=$((SIZE * 1024))
+		SIZE=$(((RANDOM * RANDOM + MINSIZE) % MAXSIZE))
+	fi
 
-	dd if=/dev/urandom of="$name" bs=1024 count=$SIZE 2> /dev/null
+	ksize=$((SIZE / 1024))
+	rem=$((SIZE - (ksize * 1024)))
 
-	SIZE=$((RANDOM % 1024))
-	SIZE=$((SIZE + 128))
-	TSIZE=$((TSIZE + SIZE))
-	dd if=/dev/urandom conv=notrunc of="$name" bs=1 count=$SIZE 2> /dev/null
+	dd if=/dev/urandom of="$name" bs=1024 count=$ksize 2> /dev/null
+	dd if=/dev/urandom conv=notrunc of="$name" bs=1 count=$rem 2> /dev/null
 	echo -e "\nMPTCP_TEST_FILE_END_MARKER" >> "$name"
 
-	echo "Created $name (size $TSIZE) containing data sent by $who"
+	echo "Created $name (size $(du -b "$name")) containing data sent by $who"
 }
 
 run_tests_lo()
@@ -497,10 +512,12 @@ run_tests_lo()
 		return 1
 	fi
 
+	if [ $do_tcp -eq 0 ]; then
 		# don't bother testing fallback tcp except for loopback case.
 		if [ ${listener_ns} != ${connector_ns} ]; then
 			return 0
 		fi
+	fi
 
 	do_transfer ${listener_ns} ${connector_ns} MPTCP TCP ${connect_addr} ${local_addr}
 	lret=$?
@@ -516,6 +533,15 @@ run_tests_lo()
 		return 1
 	fi
 
+	if [ $do_tcp -gt 1 ] ;then
+		do_transfer ${listener_ns} ${connector_ns} TCP TCP ${connect_addr} ${local_addr}
+		lret=$?
+		if [ $lret -ne 0 ]; then
+			ret=$lret
+			return 1
+		fi
+	fi
+
 	return 0
 }