1 #!/bin/bash
2
3 # udelay() test script
4 #
5 # Test is executed by writing and reading to /sys/kernel/debug/udelay_test
6 # and exercises a variety of delays to ensure that udelay() is delaying
7 # at least as long as requested (as compared to ktime).
8 #
9 # Copyright (C) 2014 Google, Inc.
10 #
11 # This software is licensed under the terms of the GNU General Public
12 # License version 2, as published by the Free Software Foundation, and
13 # may be copied, distributed, and modified under those terms.
14 #
15 # This program is distributed in the hope that it will be useful,
16 # but WITHOUT ANY WARRANTY; without even the implied warranty of
17 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 # GNU General Public License for more details.
19
20 MODULE_NAME=udelay_test
21 UDELAY_PATH=/sys/kernel/debug/udelay_test
22
23 setup()
24 {
25 /sbin/modprobe -q $MODULE_NAME
26 tmp_file=`mktemp`
27 }
28
29 test_one()
30 {
31 delay=$1
32 echo $delay > $UDELAY_PATH
33 tee -a $tmp_file < $UDELAY_PATH
34 }
35
36 cleanup()
37 {
38 if [ -f $tmp_file ]; then
39 rm $tmp_file
40 fi
41 /sbin/modprobe -q -r $MODULE_NAME
42 }
43
44 trap cleanup EXIT
45 setup
46
47 # Delay for a variety of times.
48 # 1..200, 200..500 (by 10), 500..2000 (by 100)
49 for (( delay = 1; delay < 200; delay += 1 )); do
50 test_one $delay
51 done
52 for (( delay = 200; delay < 500; delay += 10 )); do
53 test_one $delay
54 done
55 for (( delay = 500; delay <= 2000; delay += 100 )); do
56 test_one $delay
57 done
58
59 # Search for failures
60 count=`grep -c FAIL $tmp_file`
61 if [ $? -eq "0" ]; then
62 echo "ERROR: $count delays failed to delay long enough"
63 retcode=1
64 fi
65
66 exit $retcode
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.