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Revision d9a047aeffcef5755952d18f2901d8777d84019d authored by Doug Ledford on 09 July 2015, 14:21:08 UTC, committed by Doug Ledford on 14 July 2015, 17:20:15 UTC 
IB/mlx4: Optimize do_slave_init
 
There is little chance our memory allocation will fail, so we can
combine initializing the work structs with allocating them instead of
looping through all of them once to allocate and again to initialize.
Then when we need to actually find out if our device is up or in the
process of going down, have all of our work structs batched up, take the
spin_lock once and only once, and do all of the batch under the one
spin_lock invocation instead of incurring all of the locked memory cycles
we would otherwise incur to take/release the spin_lock over and over
again.

Signed-off-by: Doug Ledford <dledford@redhat.com>
1 parent 9bbf282
Raw File
udelay_test.sh 
#!/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
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