diff mbox series

[lttng-tools] Fix: test code assumes that child process is schedule to run before parent

Message ID 20210401163710.839365-1-wallinux@gmail.com
State New
Headers show
Series [lttng-tools] Fix: test code assumes that child process is schedule to run before parent | expand

Commit Message

Anders Wallin April 1, 2021, 4:37 p.m. UTC
the following tests fails
- test_event_vpid_tracker ust 0 "${EVENT_NAME}"
- test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
- test_event_pid_tracker ust 0 "${EVENT_NAME}"
- test_event_pid_track_untrack ust 0 "${EVENT_NAME}"

Signed-off-by: Anders Wallin <wallinux at gmail.com>
---
 tests/regression/tools/tracker/test_event_tracker | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

Comments

Mathieu Desnoyers April 7, 2021, 3:31 p.m. UTC | #1
----- On Apr 1, 2021, at 12:37 PM, lttng-dev lttng-dev at lists.lttng.org wrote:

> the following tests fails
> - test_event_vpid_tracker ust 0 "${EVENT_NAME}"
> - test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
> - test_event_pid_tracker ust 0 "${EVENT_NAME}"
> - test_event_pid_track_untrack ust 0 "${EVENT_NAME}"

There is indeed an issue with these tests: there is a missing "untrack all pids"
which should be done at the very beginning of each test to have the expected
behavior. AFAIU this explains why there is a small window where traced applications
can generate events when none are expected.

Fixing this should solve the issues without requiring any addition to the test
program.

Thanks,

Mathieu

> 
> Signed-off-by: Anders Wallin <wallinux at gmail.com>
> ---
> tests/regression/tools/tracker/test_event_tracker | 15 ++++++---------
> 1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/tests/regression/tools/tracker/test_event_tracker
> b/tests/regression/tools/tracker/test_event_tracker
> index 711690af..78e9310b 100755
> --- a/tests/regression/tools/tracker/test_event_tracker
> +++ b/tests/regression/tools/tracker/test_event_tracker
> @@ -5,7 +5,7 @@
> #
> # SPDX-License-Identifier: GPL-2.0-only
> 
> -TEST_DESC="LTTng - Event traker test"
> +TEST_DESC="LTTng - Event tracker test"
> 
> CURDIR=$(dirname "$0")/
> TESTDIR="$CURDIR/../../.."
> @@ -30,27 +30,24 @@ SCRIPT_GROUPNAME="$(id -gn)"
> 
> CHILD_PID=-1
> WAIT_PATH=
> -AFTER_FIRST_PATH=
> -BEFORE_LAST_PATH=
> +BEFORE_FIRST_PATH=
> 
> source $TESTDIR/utils/utils.sh
> 
> function prepare_ust_app
> {
> -	AFTER_FIRST_PATH=$(mktemp -u)
> -	BEFORE_LAST_PATH=$(mktemp -u)
> +	BEFORE_FIRST_PATH=$(mktemp -u)
> 
> -	$TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT -a "$AFTER_FIRST_PATH" -b
> "$BEFORE_LAST_PATH" &
> +	$TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT --sync-before-first-event
> "$BEFORE_FIRST_PATH" &
> 	CHILD_PID=$!
> }
> 
> function trace_ust_app
> {
> -	touch "$BEFORE_LAST_PATH"
> +	touch "$BEFORE_FIRST_PATH"
> 	wait
> 	ok $? "Traced application stopped."
> -	rm "$BEFORE_LAST_PATH"
> -	rm "$AFTER_FIRST_PATH"
> +	rm "$BEFORE_FIRST_PATH"
> }
> 
> function prepare_kernel_app
> --
> 2.31.1
> 
> _______________________________________________
> lttng-dev mailing list
> lttng-dev at lists.lttng.org
> https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
Anders Wallin April 8, 2021, 9:22 a.m. UTC | #2
OK,

I tried this and for
- test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
- test_event_pid_track_untrack ust 0 "${EVENT_NAME}"
it works well.

For
- test_event_vpid_tracker ust 0 "${EVENT_NAME}"
- test_event_pid_tracker ust 0 "${EVENT_NAME}"
validate_trace_empty fails since there is no data at all in the trace_path

This run is just calling copy of test_event_tracker running only
"test_event_vpid_tracker ust 0 ..."
1..747
# LTTng - Event tracker test
ok 1 - Start session daemon
# Test UST tracker
ok 2 - Create session tracker in -o /tmp/tmp.lu5aeCJhQ3
ok 3 - Enable ust event tp:tptest for session tracker
ok 4 - Untrack command with opts: -u --all --vpid
ok 5 - Start tracing for session
ok 6 - Track command with opts: -u --vpid 11842
ok 7 - Traced application stopped.
ok 8 - Stop lttng tracing for session
ok 9 - Destroy session tracker


*not ok 10 - Failed to parse trace#   Failed test 'Failed to parse trace'*#
  in ./regression/tools/tracker//../../../utils/tap/tap.sh:fail() at line
159.
# Killing (signal SIGTERM) lttng-sessiond and lt-lttng-sessiond pids: 11808
11809 11830
ok 11 - Wait after kill session daemon
# Looks like you planned 747 tests but only ran 11.
# Looks like you failed 1 test of 11.

# find /tmp/tmp.lu5aeCJhQ3
/tmp/tmp.lu5aeCJhQ3
/tmp/tmp.lu5aeCJhQ3/ust

Do you want me to add a special version of "validate_trace_empty" not
returning
"Failed to parse trace" for this? If so should it be added in
"test_event_tracker" or in "utils.sh"

Anders Wallin


On Wed, Apr 7, 2021 at 5:31 PM Mathieu Desnoyers <
mathieu.desnoyers at efficios.com> wrote:

> ----- On Apr 1, 2021, at 12:37 PM, lttng-dev lttng-dev at lists.lttng.org
> wrote:
>
> > the following tests fails
> > - test_event_vpid_tracker ust 0 "${EVENT_NAME}"
> > - test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
> > - test_event_pid_tracker ust 0 "${EVENT_NAME}"
> > - test_event_pid_track_untrack ust 0 "${EVENT_NAME}"
>
> There is indeed an issue with these tests: there is a missing "untrack all
> pids"
> which should be done at the very beginning of each test to have the
> expected
> behavior. AFAIU this explains why there is a small window where traced
> applications
> can generate events when none are expected.
>
> Fixing this should solve the issues without requiring any addition to the
> test
> program.
>
> Thanks,
>
> Mathieu
>
> >
> > Signed-off-by: Anders Wallin <wallinux at gmail.com>
> > ---
> > tests/regression/tools/tracker/test_event_tracker | 15 ++++++---------
> > 1 file changed, 6 insertions(+), 9 deletions(-)
> >
> > diff --git a/tests/regression/tools/tracker/test_event_tracker
> > b/tests/regression/tools/tracker/test_event_tracker
> > index 711690af..78e9310b 100755
> > --- a/tests/regression/tools/tracker/test_event_tracker
> > +++ b/tests/regression/tools/tracker/test_event_tracker
> > @@ -5,7 +5,7 @@
> > #
> > # SPDX-License-Identifier: GPL-2.0-only
> >
> > -TEST_DESC="LTTng - Event traker test"
> > +TEST_DESC="LTTng - Event tracker test"
> >
> > CURDIR=$(dirname "$0")/
> > TESTDIR="$CURDIR/../../.."
> > @@ -30,27 +30,24 @@ SCRIPT_GROUPNAME="$(id -gn)"
> >
> > CHILD_PID=-1
> > WAIT_PATH=
> > -AFTER_FIRST_PATH=
> > -BEFORE_LAST_PATH=
> > +BEFORE_FIRST_PATH=
> >
> > source $TESTDIR/utils/utils.sh
> >
> > function prepare_ust_app
> > {
> > -     AFTER_FIRST_PATH=$(mktemp -u)
> > -     BEFORE_LAST_PATH=$(mktemp -u)
> > +     BEFORE_FIRST_PATH=$(mktemp -u)
> >
> > -     $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT -a "$AFTER_FIRST_PATH" -b
> > "$BEFORE_LAST_PATH" &
> > +     $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT --sync-before-first-event
> > "$BEFORE_FIRST_PATH" &
> >       CHILD_PID=$!
> > }
> >
> > function trace_ust_app
> > {
> > -     touch "$BEFORE_LAST_PATH"
> > +     touch "$BEFORE_FIRST_PATH"
> >       wait
> >       ok $? "Traced application stopped."
> > -     rm "$BEFORE_LAST_PATH"
> > -     rm "$AFTER_FIRST_PATH"
> > +     rm "$BEFORE_FIRST_PATH"
> > }
> >
> > function prepare_kernel_app
> > --
> > 2.31.1
> >
> > _______________________________________________
> > lttng-dev mailing list
> > lttng-dev at lists.lttng.org
> > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
>
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Mathieu Desnoyers April 8, 2021, 12:48 p.m. UTC | #3
----- On Apr 8, 2021, at 5:22 AM, Anders Wallin <wallinux at gmail.com> wrote: 

> OK,

> I tried this and for
> - test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
> - test_event_pid_track_untrack ust 0 "${EVENT_NAME}"
> it works well.

> For
> - test_event_vpid_tracker ust 0 "${EVENT_NAME}"
> - test_event_pid_tracker ust 0 "${EVENT_NAME}"
> validate_trace_empty fails since there is no data at all in the trace_path

> This run is just calling copy of test_event_tracker running only
> "test_event_vpid_tracker ust 0 ..."
> 1..747
> # LTTng - Event tracker test
> ok 1 - Start session daemon
> # Test UST tracker
> ok 2 - Create session tracker in -o /tmp/tmp.lu5aeCJhQ3
> ok 3 - Enable ust event tp:tptest for session tracker
> ok 4 - Untrack command with opts: -u --all --vpid
> ok 5 - Start tracing for session
> ok 6 - Track command with opts: -u --vpid 11842
> ok 7 - Traced application stopped.
> ok 8 - Stop lttng tracing for session
> ok 9 - Destroy session tracker
> not ok 10 - Failed to parse trace
> # Failed test 'Failed to parse trace'
> # in ./regression/tools/tracker//../../../utils/tap/tap.sh:fail() at line 159.
> # Killing (signal SIGTERM) lttng-sessiond and lt-lttng-sessiond pids: 11808
> 11809 11830
> ok 11 - Wait after kill session daemon
> # Looks like you planned 747 tests but only ran 11.
> # Looks like you failed 1 test of 11.

> # find /tmp/tmp.lu5aeCJhQ3
> /tmp/tmp.lu5aeCJhQ3
> /tmp/tmp.lu5aeCJhQ3/ust

> Do you want me to add a special version of "validate_trace_empty" not returning
> "Failed to parse trace" for this? If so should it be added in
> "test_event_tracker" or in "utils.sh"

Actually, this helper already exists in utils.sh: validate_trace_session_ust_empty (), which 
internally uses validate_directory_empty (). As you point out, we should use 
validate_trace_session_ust_empty for the validation of those test cases which populate no 
trace whatsoever. 

Thanks, 

Mathieu 

> Anders Wallin

> On Wed, Apr 7, 2021 at 5:31 PM Mathieu Desnoyers < [
> mailto:mathieu.desnoyers at efficios.com | mathieu.desnoyers at efficios.com ] >
> wrote:

>> ----- On Apr 1, 2021, at 12:37 PM, lttng-dev [ mailto:lttng-dev at lists.lttng.org
>> | lttng-dev at lists.lttng.org ] wrote:

>> > the following tests fails
>> > - test_event_vpid_tracker ust 0 "${EVENT_NAME}"
>> > - test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
>> > - test_event_pid_tracker ust 0 "${EVENT_NAME}"
>> > - test_event_pid_track_untrack ust 0 "${EVENT_NAME}"

>> There is indeed an issue with these tests: there is a missing "untrack all pids"
>> which should be done at the very beginning of each test to have the expected
>> behavior. AFAIU this explains why there is a small window where traced
>> applications
>> can generate events when none are expected.

>> Fixing this should solve the issues without requiring any addition to the test
>> program.

>> Thanks,

>> Mathieu


>>> Signed-off-by: Anders Wallin < [ mailto:wallinux at gmail.com | wallinux at gmail.com
>> > ] >
>> > ---
>> > tests/regression/tools/tracker/test_event_tracker | 15 ++++++---------
>> > 1 file changed, 6 insertions(+), 9 deletions(-)

>> > diff --git a/tests/regression/tools/tracker/test_event_tracker
>> > b/tests/regression/tools/tracker/test_event_tracker
>> > index 711690af..78e9310b 100755
>> > --- a/tests/regression/tools/tracker/test_event_tracker
>> > +++ b/tests/regression/tools/tracker/test_event_tracker
>> > @@ -5,7 +5,7 @@
>> > #
>> > # SPDX-License-Identifier: GPL-2.0-only

>> > -TEST_DESC="LTTng - Event traker test"
>> > +TEST_DESC="LTTng - Event tracker test"

>> > CURDIR=$(dirname "$0")/
>> > TESTDIR="$CURDIR/../../.."
>> > @@ -30,27 +30,24 @@ SCRIPT_GROUPNAME="$(id -gn)"

>> > CHILD_PID=-1
>> > WAIT_PATH=
>> > -AFTER_FIRST_PATH=
>> > -BEFORE_LAST_PATH=
>> > +BEFORE_FIRST_PATH=

>> > source $TESTDIR/utils/utils.sh

>> > function prepare_ust_app
>> > {
>> > - AFTER_FIRST_PATH=$(mktemp -u)
>> > - BEFORE_LAST_PATH=$(mktemp -u)
>> > + BEFORE_FIRST_PATH=$(mktemp -u)

>> > - $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT -a "$AFTER_FIRST_PATH" -b
>> > "$BEFORE_LAST_PATH" &
>> > + $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT --sync-before-first-event
>> > "$BEFORE_FIRST_PATH" &
>> > CHILD_PID=$!
>> > }

>> > function trace_ust_app
>> > {
>> > - touch "$BEFORE_LAST_PATH"
>> > + touch "$BEFORE_FIRST_PATH"
>> > wait
>> > ok $? "Traced application stopped."
>> > - rm "$BEFORE_LAST_PATH"
>> > - rm "$AFTER_FIRST_PATH"
>> > + rm "$BEFORE_FIRST_PATH"
>> > }

>> > function prepare_kernel_app
>> > --
>> > 2.31.1

>> > _______________________________________________
>> > lttng-dev mailing list
>> > [ mailto:lttng-dev at lists.lttng.org | lttng-dev at lists.lttng.org ]
>>> [ https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev |
>> > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev ]

>> --
>> Mathieu Desnoyers
>> EfficiOS Inc.
>> [ http://www.efficios.com/ | http://www.efficios.com ]
Anders Wallin April 8, 2021, 3:47 p.m. UTC | #4
Is it OK that validate_trace_session_ust_empty
and validate_trace_session_kernel_empty calls different functions?
Or is it cp/paste error?

function validate_trace_session_ust_empty()
{
validate_directory_empty "$1"/ust
}

function validate_trace_session_kernel_empty()
{
* validate_trace_empty "$1"/kernel*
}

Anders Wallin


On Thu, Apr 8, 2021 at 2:48 PM Mathieu Desnoyers <
mathieu.desnoyers at efficios.com> wrote:

>
>
> ----- On Apr 8, 2021, at 5:22 AM, Anders Wallin <wallinux at gmail.com>
> wrote:
>
> OK,
>
> I tried this and for
> - test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
> - test_event_pid_track_untrack ust 0 "${EVENT_NAME}"
> it works well.
>
> For
> - test_event_vpid_tracker ust 0 "${EVENT_NAME}"
> - test_event_pid_tracker ust 0 "${EVENT_NAME}"
> validate_trace_empty fails since there is no data at all in the trace_path
>
> This run is just calling copy of test_event_tracker running only
> "test_event_vpid_tracker ust 0 ..."
> 1..747
> # LTTng - Event tracker test
> ok 1 - Start session daemon
> # Test UST tracker
> ok 2 - Create session tracker in -o /tmp/tmp.lu5aeCJhQ3
> ok 3 - Enable ust event tp:tptest for session tracker
> ok 4 - Untrack command with opts: -u --all --vpid
> ok 5 - Start tracing for session
> ok 6 - Track command with opts: -u --vpid 11842
> ok 7 - Traced application stopped.
> ok 8 - Stop lttng tracing for session
> ok 9 - Destroy session tracker
>
>
> *not ok 10 - Failed to parse trace#   Failed test 'Failed to parse trace'*#
>   in ./regression/tools/tracker//../../../utils/tap/tap.sh:fail() at line
> 159.
> # Killing (signal SIGTERM) lttng-sessiond and lt-lttng-sessiond pids:
> 11808 11809 11830
> ok 11 - Wait after kill session daemon
> # Looks like you planned 747 tests but only ran 11.
> # Looks like you failed 1 test of 11.
>
> # find /tmp/tmp.lu5aeCJhQ3
> /tmp/tmp.lu5aeCJhQ3
> /tmp/tmp.lu5aeCJhQ3/ust
>
> Do you want me to add a special version of "validate_trace_empty" not
> returning
> "Failed to parse trace" for this? If so should it be added in
> "test_event_tracker" or in "utils.sh"
>
> Actually, this helper already exists in utils.sh:
> validate_trace_session_ust_empty (), which
> internally uses validate_directory_empty (). As you point out, we should
> use
> validate_trace_session_ust_empty for the validation of those test cases
> which populate no
> trace whatsoever.
>
> Thanks,
>
> Mathieu
>
>
> Anders Wallin
>
>
> On Wed, Apr 7, 2021 at 5:31 PM Mathieu Desnoyers <
> mathieu.desnoyers at efficios.com> wrote:
>
>> ----- On Apr 1, 2021, at 12:37 PM, lttng-dev lttng-dev at lists.lttng.org
>> wrote:
>>
>> > the following tests fails
>> > - test_event_vpid_tracker ust 0 "${EVENT_NAME}"
>> > - test_event_vpid_track_untrack ust 0 "${EVENT_NAME}"
>> > - test_event_pid_tracker ust 0 "${EVENT_NAME}"
>> > - test_event_pid_track_untrack ust 0 "${EVENT_NAME}"
>>
>> There is indeed an issue with these tests: there is a missing "untrack
>> all pids"
>> which should be done at the very beginning of each test to have the
>> expected
>> behavior. AFAIU this explains why there is a small window where traced
>> applications
>> can generate events when none are expected.
>>
>> Fixing this should solve the issues without requiring any addition to the
>> test
>> program.
>>
>> Thanks,
>>
>> Mathieu
>>
>> >
>> > Signed-off-by: Anders Wallin <wallinux at gmail.com>
>> > ---
>> > tests/regression/tools/tracker/test_event_tracker | 15 ++++++---------
>> > 1 file changed, 6 insertions(+), 9 deletions(-)
>> >
>> > diff --git a/tests/regression/tools/tracker/test_event_tracker
>> > b/tests/regression/tools/tracker/test_event_tracker
>> > index 711690af..78e9310b 100755
>> > --- a/tests/regression/tools/tracker/test_event_tracker
>> > +++ b/tests/regression/tools/tracker/test_event_tracker
>> > @@ -5,7 +5,7 @@
>> > #
>> > # SPDX-License-Identifier: GPL-2.0-only
>> >
>> > -TEST_DESC="LTTng - Event traker test"
>> > +TEST_DESC="LTTng - Event tracker test"
>> >
>> > CURDIR=$(dirname "$0")/
>> > TESTDIR="$CURDIR/../../.."
>> > @@ -30,27 +30,24 @@ SCRIPT_GROUPNAME="$(id -gn)"
>> >
>> > CHILD_PID=-1
>> > WAIT_PATH=
>> > -AFTER_FIRST_PATH=
>> > -BEFORE_LAST_PATH=
>> > +BEFORE_FIRST_PATH=
>> >
>> > source $TESTDIR/utils/utils.sh
>> >
>> > function prepare_ust_app
>> > {
>> > -     AFTER_FIRST_PATH=$(mktemp -u)
>> > -     BEFORE_LAST_PATH=$(mktemp -u)
>> > +     BEFORE_FIRST_PATH=$(mktemp -u)
>> >
>> > -     $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT -a "$AFTER_FIRST_PATH"
>> -b
>> > "$BEFORE_LAST_PATH" &
>> > +     $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT
>> --sync-before-first-event
>> > "$BEFORE_FIRST_PATH" &
>> >       CHILD_PID=$!
>> > }
>> >
>> > function trace_ust_app
>> > {
>> > -     touch "$BEFORE_LAST_PATH"
>> > +     touch "$BEFORE_FIRST_PATH"
>> >       wait
>> >       ok $? "Traced application stopped."
>> > -     rm "$BEFORE_LAST_PATH"
>> > -     rm "$AFTER_FIRST_PATH"
>> > +     rm "$BEFORE_FIRST_PATH"
>> > }
>> >
>> > function prepare_kernel_app
>> > --
>> > 2.31.1
>> >
>> > _______________________________________________
>> > lttng-dev mailing list
>> > lttng-dev at lists.lttng.org
>> > https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
>>
>> --
>> Mathieu Desnoyers
>> EfficiOS Inc.
>> http://www.efficios.com
>>
>
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
>
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diff mbox series

Patch

diff --git a/tests/regression/tools/tracker/test_event_tracker b/tests/regression/tools/tracker/test_event_tracker
index 711690af..78e9310b 100755
--- a/tests/regression/tools/tracker/test_event_tracker
+++ b/tests/regression/tools/tracker/test_event_tracker
@@ -5,7 +5,7 @@ 
 #
 # SPDX-License-Identifier: GPL-2.0-only
 
-TEST_DESC="LTTng - Event traker test"
+TEST_DESC="LTTng - Event tracker test"
 
 CURDIR=$(dirname "$0")/
 TESTDIR="$CURDIR/../../.."
@@ -30,27 +30,24 @@  SCRIPT_GROUPNAME="$(id -gn)"
 
 CHILD_PID=-1
 WAIT_PATH=
-AFTER_FIRST_PATH=
-BEFORE_LAST_PATH=
+BEFORE_FIRST_PATH=
 
 source $TESTDIR/utils/utils.sh
 
 function prepare_ust_app
 {
-	AFTER_FIRST_PATH=$(mktemp -u)
-	BEFORE_LAST_PATH=$(mktemp -u)
+	BEFORE_FIRST_PATH=$(mktemp -u)
 
-	$TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT -a "$AFTER_FIRST_PATH" -b "$BEFORE_LAST_PATH" &
+	$TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT --sync-before-first-event "$BEFORE_FIRST_PATH" &
 	CHILD_PID=$!
 }
 
 function trace_ust_app
 {
-	touch "$BEFORE_LAST_PATH"
+	touch "$BEFORE_FIRST_PATH"
 	wait
 	ok $? "Traced application stopped."
-	rm "$BEFORE_LAST_PATH"
-	rm "$AFTER_FIRST_PATH"
+	rm "$BEFORE_FIRST_PATH"
 }
 
 function prepare_kernel_app