[PATCH] tools/time: access /sys/kernel/debug/udelay_test before test.

From: Hui Su
Date: Fri Oct 16 2020 - 14:06:30 EST


before(when i did not compile udelay_test.ko):
sh@ubuntu:~/workspace/compile/tools/time$ sudo ./udelay_test.sh
./udelay_test.sh: line 25: /sys/kernel/debug/udelay_test: Permission denied
./udelay_test.sh: line 26: /sys/kernel/debug/udelay_test: No such file or directory
./udelay_test.sh: line 25: /sys/kernel/debug/udelay_test: Permission denied
./udelay_test.sh: line 26: /sys/kernel/debug/udelay_test: No such file or directory
...
about two hundreds lines.

we access '/sys/kernel/debug/udelay_test' the before starting the
udelay_test.

now(when i did not compile udelay_test.ko):
sh@ubuntu:~/workspace/linux-stable/tools/time$ sudo ./udelay_test.sh
modprobe: FATAL: Module udelay_test not found in directory /lib/modules/5.4.44
ERROR, can not access /sys/kernel/debug/udelay_test.
modprobe: FATAL: Module udelay_test not found.

Signed-off-by: Hui Su <sh_def@xxxxxxx>
---
tools/time/udelay_test.sh | 51 +++++++++++++++++++++++++--------------
1 file changed, 33 insertions(+), 18 deletions(-)

diff --git a/tools/time/udelay_test.sh b/tools/time/udelay_test.sh
index 6779d7e55d85..853ba04e4149 100755
--- a/tools/time/udelay_test.sh
+++ b/tools/time/udelay_test.sh
@@ -12,10 +12,11 @@

MODULE_NAME=udelay_test
UDELAY_PATH=/sys/kernel/debug/udelay_test
+retcode=0

setup()
{
- /sbin/modprobe -q $MODULE_NAME
+ /sbin/modprobe $MODULE_NAME
tmp_file=`mktemp`
}

@@ -31,29 +32,43 @@ cleanup()
if [ -f $tmp_file ]; then
rm $tmp_file
fi
- /sbin/modprobe -q -r $MODULE_NAME
+ /sbin/modprobe -r $MODULE_NAME
+}
+
+debug_file_exist()
+{
+ if [ ! -d "$UDELAY_PATH" ]; then
+ return 1
+ fi
+ return 0
}

trap cleanup EXIT
setup
+debug_file_exist

-# Delay for a variety of times.
-# 1..200, 200..500 (by 10), 500..2000 (by 100)
-for (( delay = 1; delay < 200; delay += 1 )); do
- test_one $delay
-done
-for (( delay = 200; delay < 500; delay += 10 )); do
- test_one $delay
-done
-for (( delay = 500; delay <= 2000; delay += 100 )); do
- test_one $delay
-done
-
-# Search for failures
-count=`grep -c FAIL $tmp_file`
-if [ $? -eq "0" ]; then
- echo "ERROR: $count delays failed to delay long enough"
+if [ $? -eq 1 ]; then
retcode=1
+ echo "ERROR, can not access $UDELAY_PATH."
+else
+ # Delay for a variety of times.
+ # 1..200, 200..500 (by 10), 500..2000 (by 100)
+ for (( delay = 1; delay < 200; delay += 1 )); do
+ test_one $delay
+ done
+ for (( delay = 200; delay < 500; delay += 10 )); do
+ test_one $delay
+ done
+ for (( delay = 500; delay <= 2000; delay += 100 )); do
+ test_one $delay
+ done
+
+ # Search for failures
+ count=`grep -c FAIL $tmp_file`
+ if [ $? -eq "0" ]; then
+ echo "ERROR: $count delays failed to delay long enough"
+ retcode=1
+ fi
fi

exit $retcode
--
2.25.1