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+#!/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