selftests/ftrace: Add a testcase for kprobe multiprobe event

#!/bin/sh

# SPDX-License-Identifier: GPL-2.0

# description: Create/delete multiprobe on kprobe event

[ -f kprobe_events ] || exit_unsupported

grep -q "Create/append/" README || exit_unsupported

# Choose 2 symbols for target

SYM1=_do_fork

SYM2=do_exit

EVENT_NAME=kprobes/testevent

DEF1="p:$EVENT_NAME $SYM1"

DEF2="p:$EVENT_NAME $SYM2"

:;: "Define an event which has 2 probes" ;:

echo $DEF1 >> kprobe_events

echo $DEF2 >> kprobe_events

cat kprobe_events | grep "$DEF1"

cat kprobe_events | grep "$DEF2"

:;: "Remove the event by name (should remove both)" ;:

echo "-:$EVENT_NAME" >> kprobe_events

test `cat kprobe_events | wc -l` -eq 0

:;: "Remove just 1 event" ;:

echo $DEF1 >> kprobe_events

echo $DEF2 >> kprobe_events

echo "-:$EVENT_NAME $SYM1" >> kprobe_events

! cat kprobe_events | grep "$DEF1"

cat kprobe_events | grep "$DEF2"

:;: "Appending different type must fail" ;:

! echo "$DEF1 \$stack" >> kprobe_events