1
2clear_trace() { # reset trace output
3    echo > trace
4}
5
6disable_tracing() { # stop trace recording
7    echo 0 > tracing_on
8}
9
10enable_tracing() { # start trace recording
11    echo 1 > tracing_on
12}
13
14reset_tracer() { # reset the current tracer
15    echo nop > current_tracer
16}
17
18reset_trigger() { # reset all current setting triggers
19    grep -v ^# events/*/*/trigger |
20    while read line; do
21        cmd=`echo $line | cut -f2- -d: | cut -f1 -d" "`
22	echo "!$cmd" > `echo $line | cut -f1 -d:`
23    done
24}
25
26reset_events_filter() { # reset all current setting filters
27    grep -v ^none events/*/*/filter |
28    while read line; do
29	echo 0 > `echo $line | cut -f1 -d:`
30    done
31}
32
33disable_events() {
34    echo 0 > events/enable
35}
36
37initialize_ftrace() { # Reset ftrace to initial-state
38# As the initial state, ftrace will be set to nop tracer,
39# no events, no triggers, no filters, no function filters,
40# no probes, and tracing on.
41    disable_tracing
42    reset_tracer
43    reset_trigger
44    reset_events_filter
45    disable_events
46    echo > set_event_pid	# event tracer is always on
47    [ -f set_ftrace_filter ] && echo | tee set_ftrace_*
48    [ -f set_graph_function ] && echo | tee set_graph_*
49    [ -f stack_trace_filter ] && echo > stack_trace_filter
50    [ -f kprobe_events ] && echo > kprobe_events
51    [ -f uprobe_events ] && echo > uprobe_events
52    enable_tracing
53}
54