# vim: set syn=sh :
#
# This script contains functions which can be useful in ktune profile scripts.
#

#
# DISK tuning
#

DISKS_DEV="$(command ls -d1 /dev/[shv]d*[a-z] 2>/dev/null)"
DISKS_SYS="$(command ls -d1 /sys/block/{sd,cciss,dm-,vd}* 2>/dev/null)"

# SATA Aggressive Link Power Management
# usage: set_disk_alpm policy
set_disk_alpm() {
	policy=$1

        for host in /sys/class/scsi_host/*; do
                if [ -f $host/ahci_port_cmd ]; then
                        port_cmd=`cat $host/ahci_port_cmd`;
                        if [ $((0x$port_cmd & 0x240000)) = 0 -a -f $host/link_power_management_policy ]; then
                                echo $policy >$host/link_power_management_policy;
                        else
                                echo "max_performance" >$host/link_power_management_policy;
                        fi
                fi
        done
}

# usage: set_disk_apm level
set_disk_apm() {
	level=$1
	for disk in $DISKS_DEV; do
		hdparm -B $level $disk &>/dev/null
	done
}

# usage: set_disk_spindown level
set_disk_spindown() {
	level=$1
	for disk in $DISKS_DEV; do
		hdparm -S $level $disk &>/dev/null
	done
}

DISK_READAHEAD_SAVE="/var/run/tuned/disk_readahead.save"

# usage: multiply_disk_readahead by
multiply_disk_readahead() {
	by=$1
	rm -f "$DISK_READAHEAD_SAVE"

	# float multiplication not supported in bash
	# bc might not be installed, python is available for sure

	for disk in $DISKS_SYS; do
		control="${disk}/queue/read_ahead_kb"
		old=$(cat $control)
		new=$(echo "print int($old*$by)" | python)
		echo "echo $old > $control" >> "$DISK_READAHEAD_SAVE" 2>/dev/null
		(echo $new > $control) &>/dev/null
	done
}

restore_disk_readahead() {
	if [ -r "$DISK_READAHEAD_SAVE" ]; then
		/bin/sh "$DISK_READAHEAD_SAVE" &>/dev/null
		rm -f "$DISK_READAHEAD_SAVE"
	fi
}

# usage: remount_disk options partition1 partition2 ...
remount_partitions() {
	options=$1
	shift

	for partition in $@; do
		mount -o remount,$options $partition
	done
}

_devices_no_write_back_cache() {
	for device in $@; do
		grep -q "write back" /sys/block/"$device"/device/scsi_disk/*/cache_type 2>/dev/null && return 1
	done
	return 0
}

_disk_barriers_remount() {
	mount_options="$1"

	lsblk -lno TYPE,KNAME,MOUNTPOINT | \
	awk '
		{ type=$1; name=$2; mountpoint=$3; }

		(type == "disk") {
				device=name
				next
		}

		(mountpoint ~ /^\// && mountpoint != "/" && mountpoint != "/boot") {
			mountpoints[mountpoint] = mountpoints[mountpoint] " " device
		}

		END {
			for (mountpoint in mountpoints) {
				print mountpoint, mountpoints[mountpoint]
			}
		}
	' | \
	while read mountpoint devices; do
		if _devices_no_write_back_cache $devices; then
			mount -o remount,"$mount_options" "$mountpoint" >/dev/null 2>&1
		fi
	done
}

# remounts all non-root and non-boot partitions with nobarrier option
# SCSI drives with write back cache are skipped
disable_disk_barriers() {
	_disk_barriers_remount nobarrier
}

# see: disable_disk_barriers
enable_disk_barriers() {
	_disk_barriers_remount barrier
}

#
# CPU tuning
#

CPUSPEED_SAVE_FILE="/var/run/tuned/ktune-cpuspeed.save"
CPUSPEED_ORIG_GOV="/var/run/tuned/ktune-cpuspeed-governor-%s.save"
CPUSPEED_STARTED="/var/run/tuned/ktune-cpuspeed-started"
CPUSPEED_CFG="/etc/sysconfig/cpuspeed"
CPUSPEED_INIT="/etc/init.d/cpuspeed"
CPUS="$(ls -d1 /sys/devices/system/cpu/cpu* | sed 's;^.*/;;' |  grep "cpu[0-9]\+")"

# set CPU governor setting and store the old settings
# usage: set_cpu_governor governor
set_cpu_governor() {
	governor=$1

	# prefer governor setting using cpuspeed daemon
	if [ -e $CPUSPEED_INIT ]; then
		if [ ! -e $CPUSPEED_SAVE_FILE -a -e $CPUSPEED_CFG ]; then
			cp -p $CPUSPEED_CFG $CPUSPEED_SAVE_FILE
			sed -e 's/^GOVERNOR=.*/GOVERNOR='$governor'/g' $CPUSPEED_SAVE_FILE > $CPUSPEED_CFG
		fi

		service cpuspeed status &> /dev/null
		[ $? -eq 3 ] && touch $CPUSPEED_STARTED || rm -f $CPUSPEED_STARTED

		service cpuspeed restart &> /dev/null

	# direct change using /sys fs
	elif [ -e /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor ]; then
		echo >&2
		echo "Suggestion: install 'cpuspeed' package to get best tuning results." >&2
		echo "Falling back to '$governor' scaling governor for all CPUs." >&2
		echo >&2

		for cpu in $CPUS; do
			gov_file=/sys/devices/system/cpu/$cpu/cpufreq/scaling_governor
			save_file=$(printf $CPUSPEED_ORIG_GOV $cpu)
			rm -f $save_file
			if [ -e $gov_file ]; then
				cat $gov_file > $save_file
				echo $governor > $gov_file
			fi
		done
	fi
}

# re-enable previous CPU governor settings
# usage: restore_cpu_governor
restore_cpu_governor() {
	if [ -e $CPUSPEED_INIT ]; then
		if [ -e $CPUSPEED_SAVE_FILE ]; then
			cp -fp $CPUSPEED_SAVE_FILE $CPUSPEED_CFG
			rm -f $CPUSPEED_SAVE_FILE
		fi

		if [ -e $CPUSPEED_STARTED ]; then
			rm -f $CPUSPEED_STARTED
			service cpuspeed stop &> /dev/null
		else
			service cpuspeed restart &> /dev/null
		fi
	elif [ -e /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor ]; then
		for cpu in $CPUS; do
			cpufreq_dir=/sys/devices/system/cpu/$cpu/cpufreq
			save_file=$(printf $CPUSPEED_ORIG_GOV $cpu)

			if [ -e $cpufreq_dir/scaling_governor ]; then
				if [ -e $save_file ]; then
					cat $save_file > $cpufreq_dir/scaling_governor
					rm -f $save_file
				else
					echo userspace > $cpufreq_dir/scaling_governor
					cat $cpufreq_dir/cpuinfo_max_freq > $cpufreq_dir/scaling_setspeed
				fi
			fi
		done
	fi
}

_cpu_multicore_powersave() {
	value=$1
	[ -e /sys/devices/system/cpu/sched_mc_power_savings ] && echo $value > /sys/devices/system/cpu/sched_mc_power_savings
}

# enable multi core power savings for low wakeup systems
enable_cpu_multicore_powersave() {
	_cpu_multicore_powersave 1
}

disable_cpu_multicore_powersave() {
	_cpu_multicore_powersave 0
}

#
# MEMORY tuning
#

THP_ENABLE="/sys/kernel/mm/redhat_transparent_hugepage/enabled"
THP_SAVE="/var/run/tuned/ktune-thp.save"

[ -e "$THP_ENABLE" ] || THP_ENABLE="/sys/kernel/mm/transparent_hugepage/enabled"

set_transparent_hugepages() {
	if [ -e $THP_ENABLE ]; then
		cut -f2 -d'[' $THP_ENABLE  | cut -f1 -d']' > $THP_SAVE
		(echo "$1" > $THP_ENABLE) &> /dev/null
	fi
}

restore_transparent_hugepages() {
	if [ -e $THP_SAVE ]; then
		(echo $(cat $THP_SAVE) > $THP_ENABLE) &> /dev/null
		rm -f $THP_SAVE
	fi
}

#
# WIFI tuning
#

# usage: _wifi_set_power_level level
_wifi_set_power_level() {
	# 0    auto, PM enabled
	# 1-5  least savings and lowest latency - most savings and highest latency
	# 6    disable power savings
	level=$1

	# apply the settings using iwpriv
	ifaces=$(cat /proc/net/wireless | grep -v '|' | sed 's@^ *\([^:]*\):.*@\1@')
	for iface in $ifaces; do
		iwpriv $iface set_power $level
	done

	# some adapters may relay on sysfs
	for i in /sys/bus/pci/devices/*/power_level; do
		(echo $level > $i) &> /dev/null
	done
}

enable_wifi_powersave() {
	_wifi_set_power_level 5
}

disable_wifi_powersave() {
	_wifi_set_power_level 0
}

#
# BLUETOOTH tuning
#

disable_bluetooth() {
	hciconfig hci0 down >/dev/null 2>&1
	lsmod | grep -q btusb && rmmod btusb
}

enable_bluetooth() {
	modprobe btusb
	hciconfig hci0 up >/dev/null 2>&1
}

#
# USB tuning
#

_usb_autosuspend() {
	value=$1
	for i in /sys/bus/usb/devices/*/power/autosuspend; do echo $value > $i; done &> /dev/null
}

enable_usb_autosuspend() {
	_usb_autosuspend 1
}

disable_usb_autosuspend() {
	_usb_autosuspend 0
}

#
# SOUND CARDS tuning
#

_snd_ac97_powersave() {
	value=$1
	[ -e /sys/module/snd_ac97_codec/parameters/power_save ] && echo $value > /sys/module/snd_ac97_codec/parameters/power_save
}

enable_snd_ac97_powersave() {
	_snd_ac97_powersave Y
}

disable_snd_ac97_powersave() {
	_snd_ac97_powersave N
}

#
# CD DRIVES tuning
#

_cd_polling() {
	[ "$1" == "1" ] && opts=--enable-polling || opts=

	cddrives=$(command ls -1 /dev/scd* 2>/dev/null)
	for i in $cddrives; do hal-disable-polling $opts --device $(readlink -f $i); done &>/dev/null
}

enable_cd_polling() {
	_cd_polling 1
}

disable_cd_polling() {
	_cd_polling 0
}

#
# SOFTWARE tuning
#

RSYSLOG_CFG="/etc/rsyslog.conf"
RSYSLOG_SAVE="/var/run/tuned/ktune-cpuspeed.save"

disable_logs_syncing() {
	cp -p $RSYSLOG_CFG $RSYSLOG_SAVE
	sed -i 's/ \/var\/log/-\/var\/log/' $RSYSLOG_CFG
}

restore_logs_syncing() {
	mv $RSYSLOG_SAVE $RSYSLOG_CFG
}

#
# HARDWARE SPECIFIC tuning
#

# Asus EEE with Intel Atom
_eee_fsb_control() {
	value=$1
	if [ -e /sys/devices/platform/eeepc/she ]; then
		echo $value > /sys/devices/platform/eeepc/she
	elif [ -e /sys/devices/platform/eeepc/cpufv ]; then
		echo $value > /sys/devices/platform/eeepc/cpufv
	fi
}

eee_set_reduced_fsb() {
	_eee_fsb_control 2
}

eee_set_normal_fsb() {
	_eee_fsb_control 1
}

#
# KTUNE ACTION PROCESSING
#

error_not_implemented() {
	echo "tuned: ktune script function '$1' is not implemented." >&2
}

# implicit actions, will be used if not provided by profile script:
#
# * start    must be implemented
# * stop     must be implemented
# * reload   runs start
# * restart  runs stop + start
# * status   returns 0

start() {
	error_not_implemented start
	return 16
}

stop() {
	error_not_implemented stop
	return 16
}

reload() {
	start
	return $?
}

restart() {
	stop && start
	return $?
}

status() {
	return 0
}

# main processing

process() {
	VAR_SUBSYS_KTUNE="/var/lock/subsys/ktune"

	case "$1" in
	start)
		[ -f "$VAR_SUBSYS_KTUNE" ] && exit 0
		start
		RETVAL=$?
		;;
	stop)
		[ -f "$VAR_SUBSYS_KTUNE" ] || exit 0
		stop
		RETVAL=$?
		;;
	reload)
		[ -f "$VAR_SUBSYS_KTUNE" ] && reload
		RETVAL=$?
		;;
	restart|force-reload)
		[ -f "$VAR_SUBSYS_KTUNE" ] && restart
		RETVAL=$?
		;;
	condrestart|try-restart)
		[ -f "$VAR_SUBSYS_KTUNE" ] || exit 0
		restart
		RETVAL=$?
		;;
	status)
		status
		RETVAL=$?
		;;
		*)
		echo $"Usage: $0 {start|stop|restart|condrestart|status}"
		RETVAL=2
		;;
	esac

	exit $RETVAL
}