tools/testing/selftests/ftrace/test.d/dynevent/add_remove_fprobe_module.tc

#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
# description: Generic dynamic event - add/remove fprobe events on module
# requires: dynamic_events "f[:[<group>/][<event>]] <func-name>[%return] [<args>]":README enabled_functions

rmmod trace-events-sample ||:
if ! modprobe trace-events-sample ; then
  echo "No trace-events sample module - please make CONFIG_SAMPLE_TRACE_EVENTS=m"
  exit_unresolved;
fi
trap "lsmod | grep -q trace_events_sample && rmmod trace-events-sample" EXIT

echo 0 > events/enable
echo > dynamic_events

FUNC1='foo_bar*'
FUNC2='vfs_read'

:;: "Save enabled functions count" ;:
ecount=`cat enabled_functions | wc -l`

count_enabled_functions() {
    count=`cat enabled_functions | wc -l`
    count=$(($count-$ecount))
    echo $count
}

:;: "Add an event on the test module" ;:
echo "f:test1 $FUNC1" >> dynamic_events
echo 1 > events/fprobes/test1/enable

:;: "Ensure it is enabled" ;:
funcs=`count_enabled_functions`
test $funcs -ne 0

:;: "Check the enabled_functions is cleared on unloading" ;:
rmmod trace-events-sample
funcs=`count_enabled_functions`
test $funcs -eq 0

:;: "Check it is kept clean" ;:
modprobe trace-events-sample
echo 1 > events/fprobes/test1/enable || echo "OK"
funcs=`count_enabled_functions`
test $funcs -eq 0

:;: "Add another event not on the test module" ;:
echo "f:test2 $FUNC2" >> dynamic_events
echo 1 > events/fprobes/test2/enable

:;: "Ensure it is enabled" ;:
ofuncs=`count_enabled_functions`
test $ofuncs -ne 0

:;: "Disable and remove the first event"
echo 0 > events/fprobes/test1/enable
echo "-:fprobes/test1" >> dynamic_events
funcs=`count_enabled_functions`
test $ofuncs -eq $funcs

:;: "Disable and remove other events" ;:
echo 0 > events/fprobes/enable
echo > dynamic_events
funcs=`count_enabled_functions`
test $funcs -eq 0

rmmod trace-events-sample

:;: "Add events on kernel and test module" ;:
modprobe trace-events-sample
echo "f:test1 $FUNC1" >> dynamic_events
echo 1 > events/fprobes/test1/enable
echo "f:test2 $FUNC2" >> dynamic_events
echo 1 > events/fprobes/test2/enable
ofuncs=`count_enabled_functions`
test $ofuncs -ne 0

:;: "Unload module (ftrace entry should be removed)" ;:
rmmod trace-events-sample
funcs=`count_enabled_functions`
test $funcs -ne 0
test $ofuncs -ne $funcs

:;: "Disable and remove core-kernel fprobe event" ;:
echo 0 > events/fprobes/test2/enable
echo "-:fprobes/test2" >> dynamic_events

:;: "Ensure ftrace is disabled." ;:
funcs=`count_enabled_functions`
test $funcs -eq 0

echo 0 > events/fprobes/enable
echo > dynamic_events

trap "" EXIT
clear_trace