Merge branch 'psample-Add-additional-metadata-attributes'

Ido Schimmel says:

====================
psample: Add additional metadata attributes

This series extends the psample module to expose additional metadata to
user space for packets sampled via act_sample. The new metadata (e.g.,
transit delay) can then be consumed by applications such as hsflowd [1]
for better network observability.

netdevsim is extended with a dummy psample implementation that
periodically reports "sampled" packets to the psample module. In
addition to testing of the psample module, it enables the development
and demonstration of user space applications (e.g., hsflowd) that are
interested in the new metadata even without access to specialized
hardware (e.g., Spectrum ASIC) that can provide it.

mlxsw is also extended to provide the new metadata to psample.

A Wireshark dissector for psample netlink packets [2] will be submitted
upstream after the kernel patches are accepted. In addition, a libpcap
capture module for psample is currently in the works. Eventually, users
should be able to run:

 # tshark -i psample

In order to consume sampled packets along with their metadata.

Series overview:

Patch #1 makes it easier to extend the metadata provided to psample

Patch #2 adds the new metadata attributes to psample

Patch #3 extends netdevsim to periodically report "sampled" packets to
psample. Various debugfs knobs are added to control the reporting

Patch #4 adds a selftest over netdevsim

Patches #5-#10 gradually add support for the new metadata in mlxsw

Patch #11 adds a selftest over mlxsw

[1] https://sflow.org/draft4_sflow_transit.txt
[2] https://gitlab.com/amitcohen1/wireshark/-/commit/3d711143024e032aef1b056dd23f0266c54fab56
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 181 insertions, 0 deletions

diff --git a/tools/testing/selftests/drivers/net/netdevsim/psample.sh b/tools/testing/selftests/drivers/net/netdevsim/psample.sh
new file mode 100755
index 000000000000..ee10b1a8933c
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/netdevsim/psample.sh
@@ -0,0 +1,181 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# This test is for checking the psample module. It makes use of netdevsim
+# which periodically generates "sampled" packets.
+
+lib_dir=$(dirname $0)/../../../net/forwarding
+
+ALL_TESTS="
+	psample_enable_test
+	psample_group_num_test
+	psample_md_test
+"
+NETDEVSIM_PATH=/sys/bus/netdevsim/
+DEV_ADDR=1337
+DEV=netdevsim${DEV_ADDR}
+DEVLINK_DEV=netdevsim/${DEV}
+SYSFS_NET_DIR=/sys/bus/netdevsim/devices/$DEV/net/
+PSAMPLE_DIR=/sys/kernel/debug/netdevsim/$DEV/psample/
+CAPTURE_FILE=$(mktemp)
+NUM_NETIFS=0
+source $lib_dir/lib.sh
+source $lib_dir/devlink_lib.sh
+
+# Available at https://github.com/Mellanox/libpsample
+require_command psample
+
+psample_capture()
+{
+	rm -f $CAPTURE_FILE
+
+	timeout 2 ip netns exec testns1 psample &> $CAPTURE_FILE
+}
+
+psample_enable_test()
+{
+	RET=0
+
+	echo 1 > $PSAMPLE_DIR/enable
+	check_err $? "Failed to enable sampling when should not"
+
+	echo 1 > $PSAMPLE_DIR/enable 2>/dev/null
+	check_fail $? "Sampling enablement succeeded when should fail"
+
+	psample_capture
+	if [ $(cat $CAPTURE_FILE | wc -l) -eq 0 ]; then
+		check_err 1 "Failed to capture sampled packets"
+	fi
+
+	echo 0 > $PSAMPLE_DIR/enable
+	check_err $? "Failed to disable sampling when should not"
+
+	echo 0 > $PSAMPLE_DIR/enable 2>/dev/null
+	check_fail $? "Sampling disablement succeeded when should fail"
+
+	psample_capture
+	if [ $(cat $CAPTURE_FILE | wc -l) -ne 0 ]; then
+		check_err 1 "Captured sampled packets when should not"
+	fi
+
+	log_test "psample enable / disable"
+}
+
+psample_group_num_test()
+{
+	RET=0
+
+	echo 1234 > $PSAMPLE_DIR/group_num
+	echo 1 > $PSAMPLE_DIR/enable
+
+	psample_capture
+	grep -q -e "group 1234" $CAPTURE_FILE
+	check_err $? "Sampled packets reported with wrong group number"
+
+	# New group number should only be used after disable / enable.
+	echo 4321 > $PSAMPLE_DIR/group_num
+
+	psample_capture
+	grep -q -e "group 4321" $CAPTURE_FILE
+	check_fail $? "Group number changed while sampling is active"
+
+	echo 0 > $PSAMPLE_DIR/enable && echo 1 > $PSAMPLE_DIR/enable
+
+	psample_capture
+	grep -q -e "group 4321" $CAPTURE_FILE
+	check_err $? "Group number did not change after restarting sampling"
+
+	log_test "psample group number"
+
+	echo 0 > $PSAMPLE_DIR/enable
+}
+
+psample_md_test()
+{
+	RET=0
+
+	echo 1 > $PSAMPLE_DIR/enable
+
+	echo 1234 > $PSAMPLE_DIR/in_ifindex
+	echo 4321 > $PSAMPLE_DIR/out_ifindex
+	psample_capture
+
+	grep -q -e "in-ifindex 1234" $CAPTURE_FILE
+	check_err $? "Sampled packets reported with wrong in-ifindex"
+
+	grep -q -e "out-ifindex 4321" $CAPTURE_FILE
+	check_err $? "Sampled packets reported with wrong out-ifindex"
+
+	echo 5 > $PSAMPLE_DIR/out_tc
+	psample_capture
+
+	grep -q -e "out-tc 5" $CAPTURE_FILE
+	check_err $? "Sampled packets reported with wrong out-tc"
+
+	echo $((2**16 - 1)) > $PSAMPLE_DIR/out_tc
+	psample_capture
+
+	grep -q -e "out-tc " $CAPTURE_FILE
+	check_fail $? "Sampled packets reported with out-tc when should not"
+
+	echo 1 > $PSAMPLE_DIR/out_tc
+	echo 10000 > $PSAMPLE_DIR/out_tc_occ_max
+	psample_capture
+
+	grep -q -e "out-tc-occ " $CAPTURE_FILE
+	check_err $? "Sampled packets not reported with out-tc-occ when should"
+
+	echo 0 > $PSAMPLE_DIR/out_tc_occ_max
+	psample_capture
+
+	grep -q -e "out-tc-occ " $CAPTURE_FILE
+	check_fail $? "Sampled packets reported with out-tc-occ when should not"
+
+	echo 10000 > $PSAMPLE_DIR/latency_max
+	psample_capture
+
+	grep -q -e "latency " $CAPTURE_FILE
+	check_err $? "Sampled packets not reported with latency when should"
+
+	echo 0 > $PSAMPLE_DIR/latency_max
+	psample_capture
+
+	grep -q -e "latency " $CAPTURE_FILE
+	check_fail $? "Sampled packets reported with latency when should not"
+
+	log_test "psample metadata"
+
+	echo 0 > $PSAMPLE_DIR/enable
+}
+
+setup_prepare()
+{
+	modprobe netdevsim &> /dev/null
+
+	echo "$DEV_ADDR 1" > ${NETDEVSIM_PATH}/new_device
+	while [ ! -d $SYSFS_NET_DIR ] ; do :; done
+
+	set -e
+
+	ip netns add testns1
+	devlink dev reload $DEVLINK_DEV netns testns1
+
+	set +e
+}
+
+cleanup()
+{
+	pre_cleanup
+	rm -f $CAPTURE_FILE
+	ip netns del testns1
+	echo "$DEV_ADDR" > ${NETDEVSIM_PATH}/del_device
+	modprobe -r netdevsim &> /dev/null
+}
+
+trap cleanup EXIT
+
+setup_prepare
+
+tests_run
+
+exit $EXIT_STATUS