[v3,2/2] tools: add script to test udelay
diff mbox series

Message ID 1402603992-12466-3-git-send-email-davidriley@chromium.org
State New, archived
Headers show
Series
  • Add test to validate udelay
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Commit Message

David Riley June 12, 2014, 8:13 p.m. UTC
This script makes use of the udelay_test module to exercise udelay()
and ensure that it is delaying long enough (as compared to ktime).

Signed-off-by: David Riley <davidriley@chromium.org>
---
 tools/time/udelay_test.sh | 66 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100755 tools/time/udelay_test.sh

Comments

Douglas Anderson June 12, 2014, 10:54 p.m. UTC | #1
David,

On Thu, Jun 12, 2014 at 1:13 PM, David Riley <davidriley@chromium.org> wrote:
> This script makes use of the udelay_test module to exercise udelay()
> and ensure that it is delaying long enough (as compared to ktime).
>
> Signed-off-by: David Riley <davidriley@chromium.org>
> ---
>  tools/time/udelay_test.sh | 66 +++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 66 insertions(+)

Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Doug Anderson <dianders@chromium.org>
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Patch
diff mbox series

diff --git a/tools/time/udelay_test.sh b/tools/time/udelay_test.sh
new file mode 100755
index 0000000..12d46b9
--- /dev/null
+++ b/tools/time/udelay_test.sh
@@ -0,0 +1,66 @@ 
+#!/bin/bash
+
+# udelay() test script
+#
+# Test is executed by writing and reading to /sys/kernel/debug/udelay_test
+# and exercises a variety of delays to ensure that udelay() is delaying
+# at least as long as requested (as compared to ktime).
+#
+# Copyright (C) 2014 Google, Inc.
+#
+# This software is licensed under the terms of the GNU General Public
+# License version 2, as published by the Free Software Foundation, and
+# may be copied, distributed, and modified under those terms.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+MODULE_NAME=udelay_test
+UDELAY_PATH=/sys/kernel/debug/udelay_test
+
+setup()
+{
+	/sbin/modprobe -q $MODULE_NAME
+	tmp_file=`mktemp`
+}
+
+test_one()
+{
+	delay=$1
+	echo $delay > $UDELAY_PATH
+	tee -a $tmp_file < $UDELAY_PATH
+}
+
+cleanup()
+{
+	if [ -f $tmp_file ]; then
+		rm $tmp_file
+	fi
+	/sbin/modprobe -q -r $MODULE_NAME
+}
+
+trap cleanup EXIT
+setup
+
+# 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
+
+exit $retcode