[BUGFIX PATCH v3 4/4] selftests/ftrace: Fix multiple kprobe testcase

From: Masami Hiramatsu
Date: Mon Nov 25 2019 - 01:57:36 EST


Fix multiple kprobe event testcase to work it correctly.
There are 2 bugfixes.
- Since `wc -l FILE` returns not only line number but also
FILE filename, following "if" statement always failed.
Fix this bug by replacing it with 'cat FILE | wc -l'
- Since "while do-done loop" block with pipeline becomes a
subshell, $N local variable is not update outside of
the loop.
Fix this bug by using actual target number (256) instead
of $N.

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
.../ftrace/test.d/kprobe/multiple_kprobes.tc | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
index 5862eee91e1d..6e3dbe5f96b7 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
@@ -20,9 +20,9 @@ while read i; do
test $N -eq 256 && break
done

-L=`wc -l kprobe_events`
-if [ $L -ne $N ]; then
- echo "The number of kprobes events ($L) is not $N"
+L=`cat kprobe_events | wc -l`
+if [ $L -ne 256 ]; then
+ echo "The number of kprobes events ($L) is not 256"
exit_fail
fi