#!/bin/bash
#
# NAME
#	failcmd.sh - run a command with injecting slab/page allocation failures
#
# SYNOPSIS
#	failcmd.sh --help
#	failcmd.sh [<options>] command [arguments]
#
# DESCRIPTION
#	Run command with injecting slab/page allocation failures by fault
#	injection.
#
#	NOTE: you need to run this script as root.
#

usage()
{
	cat >&2 <<EOF
Usage: $0 [options] command [arguments]

OPTIONS
	-p percent
	--probability=percent
		likelihood of failure injection, in percent.
		Default value is 1

	-t value
	--times=value
		specifies how many times failures may happen at most.
		Default value is 1

	--oom-kill-allocating-task=value
		set /proc/sys/vm/oom_kill_allocating_task to specified value
		before running the command.
		Default value is 1

	-h, --help
		Display a usage message and exit

	--interval=value, --space=value, --verbose=value, --task-filter=value,
	--stacktrace-depth=value, --require-start=value, --require-end=value,
	--reject-start=value, --reject-end=value, --ignore-gfp-wait=value
		See Documentation/fault-injection/fault-injection.txt for more
		information

	failslab options:
	--cache-filter=value

	fail_page_alloc options:
	--ignore-gfp-highmem=value, --min-order=value

ENVIRONMENT
	FAILCMD_TYPE
		The following values for FAILCMD_TYPE are recognized:

		failslab
			inject slab allocation failures
		fail_page_alloc
			inject page allocation failures

		If FAILCMD_TYPE is not defined, then failslab is used.
EOF
}

if [ $UID != 0 ]; then
	echo must be run as root >&2
	exit 1
fi

DEBUGFS=`mount -t debugfs | head -1 | awk '{ print $3}'`

if [ ! -d "$DEBUGFS" ]; then
	echo debugfs is not mounted >&2
	exit 1
fi

FAILCMD_TYPE=${FAILCMD_TYPE:-failslab}
FAULTATTR=$DEBUGFS/$FAILCMD_TYPE

if [ ! -d $FAULTATTR ]; then
	echo $FAILCMD_TYPE is not available >&2
	exit 1
fi

LONGOPTS=probability:,interval:,times:,space:,verbose:,task-filter:
LONGOPTS=$LONGOPTS,stacktrace-depth:,require-start:,require-end:
LONGOPTS=$LONGOPTS,reject-start:,reject-end:,oom-kill-allocating-task:,help

if [ $FAILCMD_TYPE = failslab ]; then
	LONGOPTS=$LONGOPTS,ignore-gfp-wait:,cache-filter:
elif [ $FAILCMD_TYPE = fail_page_alloc ]; then
	LONGOPTS=$LONGOPTS,ignore-gfp-wait:,ignore-gfp-highmem:,min-order:
fi

TEMP=`getopt -o p:i:t:s:v:h --long $LONGOPTS -n 'failcmd.sh' -- "$@"`

if [ $? != 0 ]; then
	usage
	exit 1
fi

eval set -- "$TEMP"

fault_attr_default()
{
	echo N > $FAULTATTR/task-filter
	echo 0 > $FAULTATTR/probability
	echo 1 > $FAULTATTR/times
}

fault_attr_default

oom_kill_allocating_task_saved=`cat /proc/sys/vm/oom_kill_allocating_task`

restore_values()
{
	fault_attr_default
	echo $oom_kill_allocating_task_saved \
		> /proc/sys/vm/oom_kill_allocating_task
}

#
# Default options
#
declare -i oom_kill_allocating_task=1
declare task_filter=Y
declare -i probability=1
declare -i times=1

while true; do
	case "$1" in
	-p|--probability)
		probability=$2
		shift 2
		;;
	-i|--interval)
		echo $2 > $FAULTATTR/interval
		shift 2
		;;
	-t|--times)
		times=$2
		shift 2
		;;
	-s|--space)
		echo $2 > $FAULTATTR/space
		shift 2
		;;
	-v|--verbose)
		echo $2 > $FAULTATTR/verbose
		shift 2
		;;
	--task-filter)
		task_filter=$2
		shift 2
		;;
	--stacktrace-depth)
		echo $2 > $FAULTATTR/stacktrace-depth
		shift 2
		;;
	--require-start)
		echo $2 > $FAULTATTR/require-start
		shift 2
		;;
	--require-end)
		echo $2 > $FAULTATTR/require-end
		shift 2
		;;
	--reject-start)
		echo $2 > $FAULTATTR/reject-start
		shift 2
		;;
	--reject-end)
		echo $2 > $FAULTATTR/reject-end
		shift 2
		;;
	--oom-kill-allocating-task)
		oom_kill_allocating_task=$2
		shift 2
		;;
	--ignore-gfp-wait)
		echo $2 > $FAULTATTR/ignore-gfp-wait
		shift 2
		;;
	--cache-filter)
		echo $2 > $FAULTATTR/cache_filter
		shift 2
		;;
	--ignore-gfp-highmem)
		echo $2 > $FAULTATTR/ignore-gfp-highmem
		shift 2
		;;
	--min-order)
		echo $2 > $FAULTATTR/min-order
		shift 2
		;;
	-h|--help)
		usage
		exit 0
		shift
		;;
	--)
		shift
		break
		;;
	esac
done

[ -z "$1" ] && exit 0

echo $oom_kill_allocating_task > /proc/sys/vm/oom_kill_allocating_task
echo $task_filter > $FAULTATTR/task-filter
echo $probability > $FAULTATTR/probability
echo $times > $FAULTATTR/times

trap "restore_values" SIGINT SIGTERM EXIT

cmd="echo 1 > /proc/self/make-it-fail && exec $@"
bash -c "$cmd"
></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>Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;</td><td class='right'>2017-02-03 14:18:39 -0800</td></tr>
<tr><th>committer</th><td>Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;</td><td class='right'>2017-02-04 00:11:08 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/sched/em_canid.c?h=nds-private-remove&amp;id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>6e978b22efa1db9f6e71b24440b5f1d93e968ee3</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/sched/em_canid.c?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>c666f7a26b860674848949e39a610222b0723f89</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/sched/em_canid.c?h=nds-private-remove&amp;id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>net/sched/em_canid.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/sched/em_canid.c?h=nds-private-remove&amp;id=3c223c19aea85d3dda1416c187915f4a30b04b1f'>3c223c19aea85d3dda1416c187915f4a30b04b1f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/sched/em_canid.c?h=nds-private-remove&amp;id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3&amp;id2=3c223c19aea85d3dda1416c187915f4a30b04b1f'>diff</a>)</td></tr></table>
<div class='commit-subject'>cpufreq: intel_pstate: Disable energy efficiency optimization</div><div class='commit-msg'>Some Kabylake desktop processors may not reach max turbo when running in
HWP mode, even if running under sustained 100% utilization.

This occurs when the HWP.EPP (Energy Performance Preference) is set to
"balance_power" (0x80) -- the default on most systems.

It occurs because the platform BIOS may erroneously enable an
energy-efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not
recommended to be enabled on this SKU.

On the failing systems, this BIOS issue was not discovered when the
desktop motherboard was tested with Windows, because the BIOS also
neglects to provide the ACPI/CPPC table, that Windows requires to enable
HWP, and so Windows runs in legacy P-state mode, where this setting has
no effect.

Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and
so it runs in HWP mode, exposing this incorrect BIOS configuration.

There are several ways to address this problem.

First, Linux can also run in legacy P-state mode on this system.
As intel_pstate is how Linux enables HWP, booting with
"intel_pstate=disable"
will run in acpi-cpufreq/ondemand legacy p-state mode.

Or second, the "performance" governor can be used with intel_pstate,
which will modify HWP.EPP to 0.

Or third, starting in 4.10, the
/sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference
attribute in can be updated from "balance_power" to "performance".

Or fourth, apply this patch, which fixes the erroneous setting of
MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default
configuration to function as designed.

Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Reviewed-by: Len Brown &lt;len.brown@intel.com&gt;
Cc: 4.6+ &lt;stable@vger.kernel.org&gt; # 4.6+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>Diffstat</a> (limited to 'net/sched/em_canid.c')</div><table summary='diffstat' class='diffstat'>