1clear_trace() { # reset trace output
2    echo > trace
3}
4
5disable_tracing() { # stop trace recording
6    echo 0 > tracing_on
7}
8
9enable_tracing() { # start trace recording
10    echo 1 > tracing_on
11}
12
13reset_tracer() { # reset the current tracer
14    echo nop > current_tracer
15}
16
17reset_trigger_file() {
18    # remove action triggers first
19    grep -H ':on[^:]*(' $@ |
20    while read line; do
21        cmd=`echo $line | cut -f2- -d: | cut -f1 -d"["`
22	file=`echo $line | cut -f1 -d:`
23	echo "!$cmd" >> $file
24    done
25    grep -Hv ^# $@ |
26    while read line; do
27        cmd=`echo $line | cut -f2- -d: | cut -f1 -d"["`
28	file=`echo $line | cut -f1 -d:`
29	echo "!$cmd" > $file
30    done
31}
32
33reset_trigger() { # reset all current setting triggers
34    if [ -d events/synthetic ]; then
35        reset_trigger_file events/synthetic/*/trigger
36    fi
37    reset_trigger_file events/*/*/trigger
38}
39
40reset_events_filter() { # reset all current setting filters
41    grep -v ^none events/*/*/filter |
42    while read line; do
43	echo 0 > `echo $line | cut -f1 -d:`
44    done
45}
46
47reset_ftrace_filter() { # reset all triggers in set_ftrace_filter
48    if [ ! -f set_ftrace_filter ]; then
49      return 0
50    fi
51    echo > set_ftrace_filter
52    grep -v '^#' set_ftrace_filter | while read t; do
53	tr=`echo $t | cut -d: -f2`
54	if [ "$tr" = "" ]; then
55	    continue
56	fi
57	if ! grep -q "$t" set_ftrace_filter; then
58		continue;
59	fi
60	name=`echo $t | cut -d: -f1 | cut -d' ' -f1`
61	if [ $tr = "enable_event" -o $tr = "disable_event" ]; then
62	    tr=`echo $t | cut -d: -f2-4`
63	    limit=`echo $t | cut -d: -f5`
64	else
65	    tr=`echo $t | cut -d: -f2`
66	    limit=`echo $t | cut -d: -f3`
67	fi
68	if [ "$limit" != "unlimited" ]; then
69	    tr="$tr:$limit"
70	fi
71	echo "!$name:$tr" > set_ftrace_filter
72    done
73}
74
75disable_events() {
76    echo 0 > events/enable
77}
78
79clear_synthetic_events() { # reset all current synthetic events
80    grep -v ^# synthetic_events |
81    while read line; do
82        echo "!$line" >> synthetic_events
83    done
84}
85
86clear_dynamic_events() { # reset all current dynamic events
87    again=1
88    stop=1
89    # loop mulitple times as some events require other to be removed first
90    while [ $again -eq 1 ]; do
91	stop=$((stop+1))
92	# Prevent infinite loops
93	if [ $stop -gt 10 ]; then
94	    break;
95	fi
96	again=2
97	grep -v '^#' dynamic_events|
98	while read line; do
99	    del=`echo $line | sed -e 's/^.\([^ ]*\).*/-\1/'`
100	    if ! echo "$del" >> dynamic_events; then
101		again=1
102	    fi
103	done
104    done
105}
106
107initialize_ftrace() { # Reset ftrace to initial-state
108# As the initial state, ftrace will be set to nop tracer,
109# no events, no triggers, no filters, no function filters,
110# no probes, and tracing on.
111    disable_tracing
112    reset_tracer
113    reset_trigger
114    reset_events_filter
115    reset_ftrace_filter
116    disable_events
117    clear_dynamic_events
118    [ -f set_event_pid ] && echo > set_event_pid
119    [ -f set_ftrace_pid ] && echo > set_ftrace_pid
120    [ -f set_ftrace_notrace ] && echo > set_ftrace_notrace
121    [ -f set_graph_function ] && echo | tee set_graph_*
122    [ -f stack_trace_filter ] && echo > stack_trace_filter
123    [ -f kprobe_events ] && echo > kprobe_events
124    [ -f uprobe_events ] && echo > uprobe_events
125    [ -f synthetic_events ] && echo > synthetic_events
126    [ -f snapshot ] && echo 0 > snapshot
127
128# Stop tracing while reading the trace file by default, to prevent
129# the test results while checking it and to avoid taking a long time
130# to check the result.
131    [ -f options/pause-on-trace ] && echo 1 > options/pause-on-trace
132
133    clear_trace
134    enable_tracing
135}
136
137finish_ftrace() {
138    initialize_ftrace
139# And recover it to default.
140    [ -f options/pause-on-trace ] && echo 0 > options/pause-on-trace
141}
142
143check_requires() { # Check required files and tracers
144    for i in "$@" ; do
145	p=${i%:program}
146        r=${i%:README}
147        t=${i%:tracer}
148	if [ $p != $i ]; then
149	    if ! which $p ; then
150                echo "Required program $p is not found."
151                exit_unresolved
152	    fi
153        elif [ $t != $i ]; then
154            if ! grep -wq $t available_tracers ; then
155                echo "Required tracer $t is not configured."
156                exit_unsupported
157            fi
158        elif [ "$r" != "$i" ]; then
159            if ! grep -Fq "$r" README ; then
160                echo "Required feature pattern \"$r\" is not in README."
161                exit_unsupported
162            fi
163        elif [ ! -e $i ]; then
164            echo "Required feature interface $i doesn't exist."
165            exit_unsupported
166        fi
167    done
168}
169
170LOCALHOST=127.0.0.1
171
172yield() {
173    ping $LOCALHOST -c 1 || sleep .001 || usleep 1 || sleep 1
174}
175
176# The fork function in the kernel was renamed from "_do_fork" to
177# "kernel_fork". As older tests should still work with older kernels
178# as well as newer kernels, check which version of fork is used on this
179# kernel so that the tests can use the fork function for the running kernel.
180FUNCTION_FORK=`(if grep '\bkernel_clone\b' /proc/kallsyms > /dev/null; then
181                echo kernel_clone; else echo '_do_fork'; fi)`
182
183# Since probe event command may include backslash, explicitly use printf "%s"
184# to NOT interpret it.
185ftrace_errlog_check() { # err-prefix command-with-error-pos-by-^ command-file
186    pos=$(printf "%s" "${2%^*}" | wc -c) # error position
187    command=$(printf "%s" "$2" | tr -d ^)
188    echo "Test command: $command"
189    echo > error_log
190    (! printf "%s" "$command" >> "$3" ) 2> /dev/null
191    grep "$1: error:" -A 3 error_log
192    N=$(tail -n 1 error_log | wc -c)
193    # "  Command: " and "^\n" => 13
194    test $(expr 13 + $pos) -eq $N
195}
196