selftests/ftrace: Add test to test new set_event_notrace_pid file

A new file was added to the tracing directory that will allow a user to
place a PID into it and the task associated to that PID will not have its
events traced.  If the event-fork option is enabled, then neither will the
children of that task have its events traced.

Cc: linux-kselftest@vger.kernel.org
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent ed8839e0
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
# description: event tracing - restricts events based on pid notrace filtering
# flags: instance
do_reset() {
echo > set_event
echo > set_event_pid
echo > set_event_notrace_pid
echo 0 > options/event-fork
echo 0 > events/enable
clear_trace
echo 1 > tracing_on
}
fail() { #msg
cat trace
do_reset
echo $1
exit_fail
}
count_pid() {
pid=$@
cat trace | grep -v '^#' | sed -e 's/[^-]*-\([0-9]*\).*/\1/' | grep $pid | wc -l
}
count_no_pid() {
pid=$1
cat trace | grep -v '^#' | sed -e 's/[^-]*-\([0-9]*\).*/\1/' | grep -v $pid | wc -l
}
enable_system() {
system=$1
if [ -d events/$system ]; then
echo 1 > events/$system/enable
fi
}
enable_events() {
echo 0 > tracing_on
# Enable common groups of events, as all events can allow for
# events to be traced via scheduling that we don't care to test.
enable_system syscalls
enable_system rcu
enable_system block
enable_system exceptions
enable_system irq
enable_system net
enable_system power
enable_system signal
enable_system sock
enable_system timer
enable_system thermal
echo 1 > tracing_on
}
if [ ! -f set_event -o ! -d events/sched ]; then
echo "event tracing is not supported"
exit_unsupported
fi
if [ ! -f set_event_pid -o ! -f set_event_notrace_pid ]; then
echo "event pid notrace filtering is not supported"
exit_unsupported
fi
echo 0 > options/event-fork
do_reset
read mypid rest < /proc/self/stat
echo $mypid > set_event_notrace_pid
grep -q $mypid set_event_notrace_pid
enable_events
yield
echo 0 > tracing_on
cnt=`count_pid $mypid`
if [ $cnt -ne 0 ]; then
fail "Filtered out task has events"
fi
cnt=`count_no_pid $mypid`
if [ $cnt -eq 0 ]; then
fail "No other events were recorded"
fi
do_reset
echo $mypid > set_event_notrace_pid
echo 1 > options/event-fork
enable_events
yield &
child=$!
echo "child = $child"
wait $child
echo 0 > tracing_on
cnt=`count_pid $mypid`
if [ $cnt -ne 0 ]; then
fail "Filtered out task has events"
fi
cnt=`count_pid $child`
if [ $cnt -ne 0 ]; then
fail "Child of filtered out taskhas events"
fi
cnt=`count_no_pid $mypid`
if [ $cnt -eq 0 ]; then
fail "No other events were recorded"
fi
do_reset
exit 0
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment