From: "Steven Rostedt (VMware)" rostedt@goodmis.org

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: Steven Rostedt (VMware) rostedt@goodmis.org --- .../ftrace/test.d/event/event-no-pid.tc | 125 ++++++++++++++++++ 1 file changed, 125 insertions(+) create mode 100644 tools/testing/selftests/ftrace/test.d/event/event-no-pid.tc

diff --git a/tools/testing/selftests/ftrace/test.d/event/event-no-pid.tc b/tools/testing/selftests/ftrace/test.d/event/event-no-pid.tc new file mode 100644 index 000000000000..f0f366f18d0c --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/event/event-no-pid.tc @@ -0,0 +1,125 @@ +#!/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