[PATCH v2] selftests/ftrace: Stop tracing while reading the trace file by default

[Masami Hiramatsu <mhiramat@kernel.org>]

Stop tracing while reading the trace file by default, to prevent
the test results while checking it and to avoid taking a long time
to check the result.
If there is any testcase which wants to test the tracing while reading
the trace file, please override this setting inside the test case.

This also recovers the pause-on-trace when clean it up.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
 Changes in v2:
  - Recover pause-on-trace to 0 when exit.
---
 tools/testing/selftests/ftrace/ftracetest       |    2 +-
 tools/testing/selftests/ftrace/test.d/functions |   12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ftrace/ftracetest b/tools/testing/selftests/ftrace/ftracetest
index 8ec1922e974e..c3311c8c4089 100755
--- a/tools/testing/selftests/ftrace/ftracetest
+++ b/tools/testing/selftests/ftrace/ftracetest
@@ -428,7 +428,7 @@ for t in $TEST_CASES; do
     exit 1
   fi
 done
-(cd $TRACING_DIR; initialize_ftrace) # for cleanup
+(cd $TRACING_DIR; finish_ftrace) # for cleanup
 
 prlog ""
 prlog "# of passed: " `echo $PASSED_CASES | wc -w`
diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions
index 000fd05e84b1..5f6cbec847fc 100644
--- a/tools/testing/selftests/ftrace/test.d/functions
+++ b/tools/testing/selftests/ftrace/test.d/functions
@@ -124,10 +124,22 @@ initialize_ftrace() { # Reset ftrace to initial-state
     [ -f uprobe_events ] && echo > uprobe_events
     [ -f synthetic_events ] && echo > synthetic_events
     [ -f snapshot ] && echo 0 > snapshot
+
+# Stop tracing while reading the trace file by default, to prevent
+# the test results while checking it and to avoid taking a long time
+# to check the result.
+    [ -f options/pause-on-trace ] && echo 1 > options/pause-on-trace
+
     clear_trace
     enable_tracing
 }
 
+finish_ftrace() {
+    initialize_ftrace
+# And recover it to default.
+    [ -f options/pause-on-trace ] && echo 0 > options/pause-on-trace
+}
+
 check_requires() { # Check required files and tracers
     for i in "$@" ; do
         r=${i%:README}