Merge branch 'veth-flexible-channel-numbers'

Paolo Abeni says:

====================
veth: more flexible channels number configuration

XDP setups can benefit from multiple veth RX/TX queues. Currently
veth allow setting such number only at creation time via the
'numrxqueues' and 'numtxqueues' parameters.

This series introduces support for the ethtool set_channel operation
and allows configuring the queue number via a new module parameter.

The veth default configuration is not changed.

Finally self-tests are updated to check the new features, with both
valid and invalid arguments.

This iteration is a rebase of the most recent RFC, it does not provide
a module parameter to configure the default number of queues, but I
think could be worthy

RFC v1 -> RFC v2:
 - report more consistent 'combined' count
 - make set_channel as resilient as possible to errors
 - drop module parameter - but I would still consider it.
 - more self-tests
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/veth.sh

@@ -13,7 +13,7 @@ readonly NS_DST=$BASE$DST
 readonly BM_NET_V4=192.168.1.
 readonly BM_NET_V6=2001:db8::
 
-readonly NPROCS=`nproc`
+readonly CPUS=`nproc`
 ret=0
 
 cleanup() {
@@ -75,6 +75,29 @@ chk_tso_flag() {
 	__chk_flag "$1" $2 $3 tcp-segmentation-offload
 }
 
+chk_channels() {
+	local msg="$1"
+	local target=$2
+	local rx=$3
+	local tx=$4
+
+	local dev=veth$target
+
+	local cur_rx=`ip netns exec $BASE$target ethtool -l $dev |\
+		grep RX: | tail -n 1 | awk '{print $2}' `
+		local cur_tx=`ip netns exec $BASE$target ethtool -l $dev |\
+		grep TX: | tail -n 1 | awk '{print $2}'`
+	local cur_combined=`ip netns exec $BASE$target ethtool -l $dev |\
+		grep Combined: | tail -n 1 | awk '{print $2}'`
+
+	printf "%-60s" "$msg"
+	if [ "$cur_rx" = "$rx" -a "$cur_tx" = "$tx" -a "$cur_combined" = "n/a" ]; then
+		echo " ok "
+	else
+		echo " fail rx:$rx:$cur_rx tx:$tx:$cur_tx combined:n/a:$cur_combined"
+	fi
+}
+
 chk_gro() {
 	local msg="$1"
 	local expected=$2
@@ -107,11 +130,100 @@ chk_gro() {
 	fi
 }
 
+__change_channels()
+{
+	local cur_cpu
+	local end=$1
+	local cur
+	local i
+
+	while true; do
+		printf -v cur '%(%s)T'
+		[ $cur -le $end ] || break
+
+		for i in `seq 1 $CPUS`; do
+			ip netns exec $NS_SRC ethtool -L veth$SRC rx $i tx $i
+			ip netns exec $NS_DST ethtool -L veth$DST rx $i tx $i
+		done
+
+		for i in `seq 1 $((CPUS - 1))`; do
+			cur_cpu=$((CPUS - $i))
+			ip netns exec $NS_SRC ethtool -L veth$SRC rx $cur_cpu tx $cur_cpu
+			ip netns exec $NS_DST ethtool -L veth$DST rx $cur_cpu tx $cur_cpu
+		done
+	done
+}
+
+__send_data() {
+	local end=$1
+
+	while true; do
+		printf -v cur '%(%s)T'
+		[ $cur -le $end ] || break
+
+		ip netns exec $NS_SRC ./udpgso_bench_tx -4 -s 1000 -M 300 -D $BM_NET_V4$DST
+	done
+}
+
+do_stress() {
+	local end
+	printf -v end '%(%s)T'
+	end=$((end + $STRESS))
+
+	ip netns exec $NS_SRC ethtool -L veth$SRC rx 3 tx 3
+	ip netns exec $NS_DST ethtool -L veth$DST rx 3 tx 3
+
+	ip netns exec $NS_DST ./udpgso_bench_rx &
+	local rx_pid=$!
+
+	echo "Running stress test for $STRESS seconds..."
+	__change_channels $end &
+	local ch_pid=$!
+	__send_data $end &
+	local data_pid_1=$!
+	__send_data $end &
+	local data_pid_2=$!
+	__send_data $end &
+	local data_pid_3=$!
+	__send_data $end &
+	local data_pid_4=$!
+
+	wait $ch_pid $data_pid_1 $data_pid_2 $data_pid_3 $data_pid_4
+	kill -9 $rx_pid
+	echo "done"
+
+	# restore previous setting
+	ip netns exec $NS_SRC ethtool -L veth$SRC rx 2 tx 2
+	ip netns exec $NS_DST ethtool -L veth$DST rx 2 tx 1
+}
+
+usage() {
+	echo "Usage: $0 [-h] [-s <seconds>]"
+	echo -e "\t-h: show this help"
+	echo -e "\t-s: run optional stress tests for the given amount of seconds"
+}
+
+STRESS=0
+while getopts "hs:" option; do
+	case "$option" in
+	"h")
+		usage $0
+		exit 0
+		;;
+	"s")
+		STRESS=$OPTARG
+		;;
+	esac
+done
+
 if [ ! -f ../bpf/xdp_dummy.o ]; then
 	echo "Missing xdp_dummy helper. Build bpf selftest first"
 	exit 1
 fi
 
+[ $CPUS -lt 2 ] && echo "Only one CPU available, some tests will be skipped"
+[ $STRESS -gt 0 -a $CPUS -lt 3 ] && echo " stress test will be skipped, too"
+
 create_ns
 chk_gro_flag "default - gro flag" $SRC off
 chk_gro_flag "        - peer gro flag" $DST off
@@ -134,6 +246,8 @@ chk_gro "        - aggregation with TSO off" 1
 cleanup
 
 create_ns
+chk_channels "default channels" $DST 1 1
+
 ip -n $NS_DST link set dev veth$DST down
 ip netns exec $NS_DST ethtool -K veth$DST gro on
 chk_gro_flag "with gro enabled on link down - gro flag" $DST on
@@ -147,6 +261,56 @@ chk_gro "        - aggregation with TSO off" 1
 cleanup
 
 create_ns
+
+CUR_TX=1
+CUR_RX=1
+if [ $CPUS -gt 1 ]; then
+	ip netns exec $NS_DST ethtool -L veth$DST tx 2
+	chk_channels "setting tx channels" $DST 1 2
+	CUR_TX=2
+fi
+
+if [ $CPUS -gt 2 ]; then
+	ip netns exec $NS_DST ethtool -L veth$DST rx 3 tx 3
+	chk_channels "setting both rx and tx channels" $DST 3 3
+	CUR_RX=3
+	CUR_TX=3
+fi
+
+ip netns exec $NS_DST ethtool -L veth$DST combined 2 2>/dev/null
+chk_channels "bad setting: combined channels" $DST $CUR_RX $CUR_TX
+
+ip netns exec $NS_DST ethtool -L veth$DST tx $((CPUS + 1)) 2>/dev/null
+chk_channels "setting invalid channels nr" $DST $CUR_RX $CUR_TX
+
+if [ $CPUS -gt 1 ]; then
+	# this also tests queues nr reduction
+	ip netns exec $NS_DST ethtool -L veth$DST rx 1 tx 2 2>/dev/null
+	ip netns exec $NS_SRC ethtool -L veth$SRC rx 1 tx 2 2>/dev/null
+	printf "%-60s" "bad setting: XDP with RX nr less than TX"
+	ip -n $NS_DST link set dev veth$DST xdp object ../bpf/xdp_dummy.o \
+		section xdp_dummy 2>/dev/null &&\
+		echo "fail - set operation successful ?!?" || echo " ok "
+
+	# the following tests will run with multiple channels active
+	ip netns exec $NS_SRC ethtool -L veth$SRC rx 2
+	ip netns exec $NS_DST ethtool -L veth$DST rx 2
+	ip -n $NS_DST link set dev veth$DST xdp object ../bpf/xdp_dummy.o \
+		section xdp_dummy 2>/dev/null
+	printf "%-60s" "bad setting: reducing RX nr below peer TX with XDP set"
+	ip netns exec $NS_DST ethtool -L veth$DST rx 1 2>/dev/null &&\
+		echo "fail - set operation successful ?!?" || echo " ok "
+	CUR_RX=2
+	CUR_TX=2
+fi
+
+if [ $CPUS -gt 2 ]; then
+	printf "%-60s" "bad setting: increasing peer TX nr above RX with XDP set"
+	ip netns exec $NS_SRC ethtool -L veth$SRC tx 3 2>/dev/null &&\
+		echo "fail - set operation successful ?!?" || echo " ok "
+	chk_channels "setting invalid channels nr" $DST 2 2
+fi
+
 ip -n $NS_DST link set dev veth$DST xdp object ../bpf/xdp_dummy.o section xdp_dummy 2>/dev/null
 chk_gro_flag "with xdp attached - gro flag" $DST on
 chk_gro_flag "        - peer gro flag" $SRC off
@@ -167,10 +331,27 @@ chk_gro_flag "        - after gro on xdp off, gro flag" $DST on
 chk_gro_flag "        - peer gro flag" $SRC off
 chk_tso_flag "        - tso flag" $SRC on
 chk_tso_flag "        - peer tso flag" $DST on
+
+if [ $CPUS -gt 1 ]; then
+	ip netns exec $NS_DST ethtool -L veth$DST tx 1
+	chk_channels "decreasing tx channels with device down" $DST 2 1
+fi
+
 ip -n $NS_DST link set dev veth$DST up
 ip -n $NS_SRC link set dev veth$SRC up
 chk_gro "        - aggregation" 1
 
+if [ $CPUS -gt 1 ]; then
+	[ $STRESS -gt 0 -a $CPUS -gt 2 ] && do_stress
+
+	ip -n $NS_DST link set dev veth$DST down
+	ip -n $NS_SRC link set dev veth$SRC down
+	ip netns exec $NS_DST ethtool -L veth$DST tx 2
+	chk_channels "increasing tx channels with device down" $DST 2 2
+	ip -n $NS_DST link set dev veth$DST up
+	ip -n $NS_SRC link set dev veth$SRC up
+fi
+
 ip netns exec $NS_DST ethtool -K veth$DST gro off
 ip netns exec $NS_SRC ethtool -K veth$SRC tx-udp-segmentation off
 chk_gro "aggregation again with default and TSO off" 10