#!/bin/bash
#
# Alternate sleeping and spinning on randomly selected CPUs.  The purpose
# of this script is to inflict random OS jitter on a concurrently running
# test.
#
# Usage: jitter.sh me duration [ sleepmax [ spinmax ] ]
#
# me: Random-number-generator seed salt.
# duration: Time to run in seconds.
# sleepmax: Maximum microseconds to sleep, defaults to one second.
# spinmax: Maximum microseconds to spin, defaults to one millisecond.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# 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.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, you can access it online at
# http://www.gnu.org/licenses/gpl-2.0.html.
#
# Copyright (C) IBM Corporation, 2016
#
# Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

me=$(($1 * 1000))
duration=$2
sleepmax=${3-1000000}
spinmax=${4-1000}

n=1

starttime=`awk 'BEGIN { print systime(); }' < /dev/null`

while :
do
	# Check for done.
	t=`awk -v s=$starttime 'BEGIN { print systime() - s; }' < /dev/null`
	if test "$t" -gt "$duration"
	then
		exit 0;
	fi

	# Set affinity to randomly selected CPU
	cpus=`ls /sys/devices/system/cpu/*/online |
		sed -e 's,/[^/]*$,,' -e 's/^[^0-9]*//' |
		grep -v '^0*$'`
	cpumask=`awk -v cpus="$cpus" -v me=$me -v n=$n 'BEGIN {
		srand(n + me + systime());
		ncpus = split(cpus, ca);
		curcpu = ca[int(rand() * ncpus + 1)];
		mask = lshift(1, curcpu);
		if (mask + 0 <= 0)
			mask = 1;
		printf("%#x\n", mask);
	}' < /dev/null`
	n=$(($n+1))
	if ! taskset -p $cpumask $$ > /dev/null 2>&1
	then
		echo taskset failure: '"taskset -p ' $cpumask $$ '"'
		exit 1
	fi

	# Sleep a random duration
	sleeptime=`awk -v me=$me -v n=$n -v sleepmax=$sleepmax 'BEGIN {
		srand(n + me + systime());
		printf("%06d", int(rand() * sleepmax));
	}' < /dev/null`
	n=$(($n+1))
	sleep .$sleeptime

	# Spin a random duration
	limit=`awk -v me=$me -v n=$n -v spinmax=$spinmax 'BEGIN {
		srand(n + me + systime());
		printf("%06d", int(rand() * spinmax));
	}' < /dev/null`
	n=$(($n+1))
	for i in {1..$limit}
	do
		echo > /dev/null
	done
done

exit 1
 name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?id=96692b097ba76d0c637ae8af47b29c73da33c9d0'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound?id=96692b097ba76d0c637ae8af47b29c73da33c9d0'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/usb?id=96692b097ba76d0c637ae8af47b29c73da33c9d0'>usb</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/usb/caiaq?id=96692b097ba76d0c637ae8af47b29c73da33c9d0'>caiaq</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/usb/caiaq/audio.c?id=96692b097ba76d0c637ae8af47b29c73da33c9d0'>audio.c</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/sound/usb/caiaq/audio.c?id=96692b097ba76d0c637ae8af47b29c73da33c9d0&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
elected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-25 14:05:56 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-25 14:05:56 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/isa/wavefront?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>b272f732f888d4cf43c943a40c9aaa836f9b7431</a> (<a href='/cgit.cgi/linux/net-next.git/patch/sound/isa/wavefront?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>da9cac6b9d12b83592c16d3503c0e3f2f00f146f</a> /<a href='/cgit.cgi/linux/net-next.git/tree/sound/isa/wavefront?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>sound/isa/wavefront</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/isa/wavefront?id=10bbe7599e2755d3f3e100103967788b8b5a4bce'>10bbe7599e2755d3f3e100103967788b8b5a4bce</a> (<a href='/cgit.cgi/linux/net-next.git/diff/sound/isa/wavefront?id=b272f732f888d4cf43c943a40c9aaa836f9b7431&amp;id2=10bbe7599e2755d3f3e100103967788b8b5a4bce'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/sound/isa/wavefront?id=008b69e4d52f2cbee3ed0d0502edd78155000b1a'>008b69e4d52f2cbee3ed0d0502edd78155000b1a</a> (<a href='/cgit.cgi/linux/net-next.git/diff/sound/isa/wavefront?id=b272f732f888d4cf43c943a40c9aaa836f9b7431&amp;id2=008b69e4d52f2cbee3ed0d0502edd78155000b1a'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</div><div class='commit-msg'>Pull SMP hotplug notifier removal from Thomas Gleixner:
 "This is the final cleanup of the hotplug notifier infrastructure. The
  series has been reintgrated in the last two days because there came a
  new driver using the old infrastructure via the SCSI tree.

  Summary:

   - convert the last leftover drivers utilizing notifiers

   - fixup for a completely broken hotplug user

   - prevent setup of already used states

   - removal of the notifiers

   - treewide cleanup of hotplug state names

   - consolidation of state space

  There is a sphinx based documentation pending, but that needs review
  from the documentation folks"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/armada-xp: Consolidate hotplug state space
  irqchip/gic: Consolidate hotplug state space
  coresight/etm3/4x: Consolidate hotplug state space
  cpu/hotplug: Cleanup state names
  cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions
  staging/lustre/libcfs: Convert to hotplug state machine
  scsi/bnx2i: Convert to hotplug state machine
  scsi/bnx2fc: Convert to hotplug state machine
  cpu/hotplug: Prevent overwriting of callbacks
  x86/msr: Remove bogus cleanup from the error path
  bus: arm-ccn: Prevent hotplug callback leak
  perf/x86/intel/cstate: Prevent hotplug callback leak
  ARM/imx/mmcd: Fix broken cpu hotplug handling
  scsi: qedi: Convert to hotplug state machine
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>Diffstat</a> (limited to 'sound/isa/wavefront')</div><table summary='diffstat' class='diffstat'>