[for-next][PATCH 02/21] selftest/ftrace: Fix function trigger test to handle trace not disabling the tracer

[for-next][PATCH 02/21] selftest/ftrace: Fix function trigger test to handle trace not disabling the tracer

[Steven Rostedt]

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

The ftrace selftest "ftrace - test for function traceon/off triggers"
enables all events and reads the trace file. Now that the trace file does
not disable tracing, and will attempt to continually read new data that is
added, the selftest gets stuck reading the trace file. This is because the
data added to the trace file will fill up quicker than the reading of it.

By only enabling scheduling events, the read can keep up with the writes.
Instead of enabling all events, only enable the scheduler events.

Link: http://lkml.kernel.org/r/20200318111345.0516642e@gandalf.local.home

Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: linux-kselftest@vger.kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 .../selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc
index 0c04282d33dd..1947387fe976 100644
--- a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc
+++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc
@@ -41,7 +41,7 @@ fi
 
 echo '** ENABLE EVENTS'
 
-echo 1 > events/enable
+echo 1 > events/sched/enable
 
 echo '** ENABLE TRACING'
 enable_tracing
-- 
2.25.1

[for-next][PATCH 19/21] selftests/ftrace: Add test to test new set_ftrace_notrace_pid file

[Steven Rostedt]

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 be traced
by the function tracer. If the function-fork option is enabled, then neither
will the children of that task be traced by the function tracer.

Cc: linux-kselftest@vger.kernel.org
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
 .../test.d/ftrace/func-filter-notrace-pid.tc  | 108 ++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 tools/testing/selftests/ftrace/test.d/ftrace/func-filter-notrace-pid.tc

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-notrace-pid.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-notrace-pid.tc
new file mode 100644
index 000000000000..8aa46a2ea133
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-notrace-pid.tc
@@ -0,0 +1,108 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: ftrace - function pid notrace filters
+# flags: instance
+
+# Make sure that function pid matching filter with notrace works.
+
+if ! grep -q function available_tracers; then
+    echo "no function tracer configured"
+    exit_unsupported
+fi
+
+if [ ! -f set_ftrace_notrace_pid ]; then
+    echo "set_ftrace_notrace_pid not found? Is function tracer not set?"
+    exit_unsupported
+fi
+
+if [ ! -f set_ftrace_filter ]; then
+    echo "set_ftrace_filter not found? Is function tracer not set?"
+    exit_unsupported
+fi
+
+do_function_fork=1
+
+if [ ! -f options/function-fork ]; then
+    do_function_fork=0
+    echo "no option for function-fork found. Option will not be tested."
+fi
+
+read PID _ < /proc/self/stat
+
+if [ $do_function_fork -eq 1 ]; then
+    # default value of function-fork option
+    orig_value=`grep function-fork trace_options`
+fi
+
+do_reset() {
+    if [ $do_function_fork -eq 0 ]; then
+	return
+    fi
+
+    echo > set_ftrace_notrace_pid
+    echo $orig_value > trace_options
+}
+
+fail() { # msg
+    do_reset
+    echo $1
+    exit_fail
+}
+
+do_test() {
+    disable_tracing
+
+    echo do_execve* > set_ftrace_filter
+    echo *do_fork >> set_ftrace_filter
+
+    echo $PID > set_ftrace_notrace_pid
+    echo function > current_tracer
+
+    if [ $do_function_fork -eq 1 ]; then
+	# don't allow children to be traced
+	echo nofunction-fork > trace_options
+    fi
+
+    enable_tracing
+    yield
+
+    count_pid=`cat trace | grep -v ^# | grep $PID | wc -l`
+    count_other=`cat trace | grep -v ^# | grep -v $PID | wc -l`
+
+    # count_pid should be 0
+    if [ $count_pid -ne 0 -o $count_other -eq 0 ]; then
+	fail "PID filtering not working? traced task = $count_pid; other tasks = $count_other "
+    fi
+
+    disable_tracing
+    clear_trace
+
+    if [ $do_function_fork -eq 0 ]; then
+	return
+    fi
+
+    # allow children to be traced
+    echo function-fork > trace_options
+
+    # With pid in both set_ftrace_pid and set_ftrace_notrace_pid
+    # there should not be any tasks traced.
+
+    echo $PID > set_ftrace_pid
+
+    enable_tracing
+    yield
+
+    count_pid=`cat trace | grep -v ^# | grep $PID | wc -l`
+    count_other=`cat trace | grep -v ^# | grep -v $PID | wc -l`
+
+    # both should be zero
+    if [ $count_pid -ne 0 -o $count_other -ne 0 ]; then
+	fail "PID filtering not following fork? traced task = $count_pid; other tasks = $count_other "
+    fi
+}
+
+do_test
+
+do_reset
+
+exit 0
-- 
2.25.1

[for-next][PATCH 20/21] selftests/ftrace: Add test to test new set_event_notrace_pid file

[Steven Rostedt]

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
-- 
2.25.1