#!/bin/bash

#

# Copyright (c) 2004-2007 rncbc aka Rui Nuno Capela.

#

# /etc/init.d/rtirq

#

# Startup script for realtime-preempt enabled kernels.

#

# This program is free software; you can redistribute it and/or modify it

# under the terms of the GNU General Public License version 2 or later.

#

# chkconfig: 35 81 19

# description: Realtime IRQ thread tunning.

#

### BEGIN INIT INFO

# Provides:          rtirq

# Required-Start:    $syslog $local_fs

# Should-Start: $time alsa alsasound hotplug

# Required-Stop:     $syslog $local_fs

# Should-Stop: $time alsa alsasound hotplug

# Default-Start:     3 5

# Default-Stop:      0 1 2 6

# Short-Description: Realtime IRQ thread tunning.

# Description:       Change the realtime scheduling policy

#   and priority of relevant system driver IRQ handlers.

### END INIT INFO

#



# Won't work without those binaries.

for DIR in /sbin /usr/sbin /bin /usr/bin /usr/local/bin; do

[ -z "${RTIRQ_CHRT}" -a -x ${DIR}/chrt ] &&

RTIRQ_CHRT=${DIR}/chrt

done



# Check for missing binaries (stale symlinks should not happen)

[ -n "${RTIRQ_CHRT}" -a -x ${RTIRQ_CHRT} ] || {

echo "`basename $0`: chrt: not installed."

[ "$1" = "stop" ] && exit 0 || exit 5

}



# Check for existence of needed config file and read it.

RTIRQ_CONFIG="/etc/rtirq.conf"

[ -r ${RTIRQ_CONFIG} ] || {

echo "`basename $0`: ${RTIRQ_CONFIG}: not found."

[ "${RTIRQ_ACTION}" = "stop" ] && exit 0 || exit 6

}



# Read configuration.

. ${RTIRQ_CONFIG}



# Colon delimited trail list of already assigned IRQ numbers,

# preventind lower priority override due to shared IRQs.

RTIRQ_TRAIL=":"



#

# Reset policy of all IRQ threads out there.

#

function rtirq_reset ()

{

# Reset all softirq-timer/s from highest priority.

rtirq_exec_high reset

# PIDS=`ps -eo pid,class | egrep '(FF|RR)' | awk '{print $1}'`

PIDS=`ps -eo pid,comm | grep IRQ | awk '{print $1}'`

for PID in ${PIDS}

do

${RTIRQ_CHRT} --pid --other 0 ${PID}

done

}



#

# IRQ thread handler policy prioritizer, by IRQ number.

#

function rtirq_exec_num ()

{

ACTION=$1

NAME1=$2

NAME2=$3

PRI2=$4

IRQ=$5

# Check the services that are to be (un)threaded.

if [ -n "`echo :${RTIRQ_NON_THREADED}: | sed 's/ /:/g' | grep

:${NAME1}:`" ]

then

PREPEND="`basename $0`: ${ACTION} [${NAME2}] irq=${IRQ}"

for THREADED in /proc/irq/${IRQ}/*/threaded

do

if [ -f "${THREADED}" ]

then

case ${ACTION} in

*start)

echo "${PREPEND}: ${THREADED}: OFF."

echo -n 0 > "${THREADED}"

;;

stop)

echo "${PREPEND}: ${THREADED}: ON."

echo -n 1 > "${THREADED}"

;;

esac

fi

done

fi

# And now do the proper threading prioritization...

if [ -z "`echo ${RTIRQ_TRAIL} | grep :${IRQ}:`" ]

then

PIDS=`ps -eo pid,comm | egrep "IRQ.${IRQ}\$" | awk '{print $1}'`

for PID in ${PIDS}

do

PREPEND="`basename $0`: ${ACTION} [${NAME2}] irq=${IRQ}

pid=${PID}"

case ${ACTION} in

*start)

PREPEND="${PREPEND} prio=${PRI2}"

if ${RTIRQ_CHRT} --pid --fifo ${PRI2} ${PID}

then

echo "${PREPEND}: OK."

else

echo "${PREPEND}: FAILED."

fi

;;

stop)

if ${RTIRQ_CHRT} --pid --other 0 ${PID}

then

echo "${PREPEND}: OK."

else

echo "${PREPEND}: FAILED."

fi

;;

status)

echo "${PREPEND}: " && ${RTIRQ_CHRT} --pid --verbose ${PID}

;;

*)

echo "${PREPEND}: ERROR."

;;

esac

PRI2=$((${PRI2} - 1))

done

RTIRQ_TRAIL=":${IRQ}${RTIRQ_TRAIL}"

fi

}



#

# IRQ thread handler policy prioritizer, by service name.

#

function rtirq_exec_name ()

{

ACTION=$1

NAME1=$2

NAME2=$3

PRI1=$4

IRQS=`grep "${NAME2}" /proc/interrupts | awk -F: '{print $1}'`

for IRQ in ${IRQS}

do

rtirq_exec_num ${ACTION} ${NAME1} ${NAME2} ${PRI1} ${IRQ}

PRI1=$((${PRI1} - 1))

done

}



#

# Generic process top prioritizer

#

function rtirq_exec_high ()

{

ACTION=$1

case ${ACTION} in

*start)

PRI1=99

;;

*)

PRI1=1

;;

esac

# Process all configured process names...

for NAME in ${RTIRQ_HIGH_LIST}

do

PREPEND="`basename $0`: ${ACTION} [${NAME}]"

PIDS=`ps -eo pid,comm | grep "${NAME}" | awk '{print $1}'`

for PID in ${PIDS}

do

if ${RTIRQ_CHRT} --pid --fifo ${PRI1} ${PID}

then

echo "${PREPEND} pid=${PID} prio=${PRI1}: OK."

else

echo "${PREPEND} pid=${PID} prio=${PRI1}: FAILED."

fi

done

[ ${PRI1} -gt ${RTIRQ_PRIO_HIGH} ] && PRI1=$((${PRI1} - 1))

done

}



#

# Main executive.

#

function rtirq_exec ()

{

ACTION=$1

# Check configured base priority.

PRI0=${RTIRQ_PRIO_HIGH:-90}

[ $((${PRI0})) -gt 95 ] && PRI0=95

[ $((${PRI0})) -lt 55 ] && PRI0=55

# Check configured priority decrease step.

DECR=${RTIRQ_PRIO_DECR:-5}

[ $((${DECR})) -gt 10 ] && DECR=10

[ $((${DECR})) -lt 1 ] && DECR=1

# (Re)set all softirq-timer/s to highest priority.

rtirq_exec_high ${ACTION}

# Process all configured service names...

for NAME in ${RTIRQ_NAME_LIST}

do

case ${NAME} in

snd)

PRI1=${PRI0}

IRQS=`grep irq /proc/asound/cards | tac | sed 's/.* irq

\(.*\)/\1/'`

for IRQ in ${IRQS}

do

rtirq_exec_num ${ACTION} ${NAME} ${NAME} ${PRI1} ${IRQ}

PRI1=$((${PRI1} - 1))

done

;;

usb)

rtirq_exec_name ${ACTION} ${NAME} "ohci_hcd" ${PRI0}

rtirq_exec_name ${ACTION} ${NAME} "uhci_hcd" ${PRI0}

rtirq_exec_name ${ACTION} ${NAME} "ehci_hcd" ${PRI0}

;;

*)

rtirq_exec_name ${ACTION} ${NAME} ${NAME} ${PRI0}

;;

esac

[ ${PRI0} -gt ${DECR} ] && PRI0=$((${PRI0} - ${DECR}))

done

}



#

# Main procedure line.

#

case $1 in

*start)

if [ "${RTIRQ_RESET_ALL}" = "yes" -o "${RTIRQ_RESET_ALL}" = "1" ]

then

rtirq_reset

fi

rtirq_exec start

;;

stop)

if [ "${RTIRQ_RESET_ALL}" = "yes" -o "${RTIRQ_RESET_ALL}" = "1" ]

then

rtirq_reset

#else

# rtirq_exec stop

fi

;;

reset)

if [ "${RTIRQ_RESET_ALL}" = "yes" -o "${RTIRQ_RESET_ALL}" = "1" ]

then

rtirq_reset

else

rtirq_exec stop

fi

;;

status)

echo

#rtirq_exec status

ps -eo pid,class,rtprio,ni,pri,pcpu,stat,comm --sort -rtprio \

| egrep '(\^[[:blank:]]*PID|IRQ|softirq)' \

| awk 'BEGIN {

while (getline IRQLine < "/proc/interrupts") {

split(IRQLine, IRQSplit, ":[[:blank:]|0-9]+");

if (match(IRQSplit[1], "\^[[:blank:]]*[0-9]+$")) {

gsub("[\^[:blank:]]+PIC[\^[:blank:]]*[[:blank:]]+" \

"|\[[\^\]]+\][\^[:blank:]]*[[:blank:]]+",

"", IRQSplit[2]);

IRQTable[IRQSplit[1] + 0] = IRQSplit[2];

}

}

} { if ($9 == "")

{ print $0"\t"IRQTable[substr($8,5)]; }

else

{ print $0"\t"IRQTable[$9]; } }'

echo

;;

*)

echo

echo " Usage: $0 {[re]start|stop|reset|status}"

echo

exit 1

;;

esac



exit 0

#!/bin/sh

#

# Copyright (c) 2004-2007 rncbc aka Rui Nuno Capela.

#

# /etc/sysconfig/rtirq

#

# Configuration for IRQ thread tunning,

# for realtime-preempt enabled kernels.

#

# This program is free software; you can redistribute it and/or modify it

# under the terms of the GNU General Public License version 2 or later.

#



# IRQ thread service names

# (space separated list, from higher to lower priority).

RTIRQ_NAME_LIST="rtc snd usb i8042"



# Highest priority.

RTIRQ_PRIO_HIGH=90



# Priority decrease step.

RTIRQ_PRIO_DECR=5



# Whether to reset all IRQ threads to SCHED_OTHER.

RTIRQ_RESET_ALL=0



# On kernel configurations that support it,

# which services should be NOT threaded

# (space separated list).

RTIRQ_NON_THREADED="rtc snd"



# Process names which will be forced to the

# highest realtime priority range (99-91)

# (space separated list, from highest to lower priority).

RTIRQ_HIGH_LIST="softirq-timer"