#!/bin/bash
#
# Start/Stop the workload manager
#
# Copyright IBM Corporation. 2008
#
# Authors:     Balbir Singh <balbir@linux.vnet.ibm.com>
# This program is free software; you can redistribute it and/or modify it
# under the terms of version 2.1 of the GNU Lesser General Public License
# as published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# cgconfig Control Groups Configuration Startup
# chkconfig: - 5 95
# description: This script runs the cgconfigparser utility to parse and setup
#              the control group filesystem. It uses /etc/cgconfig.conf
#              and parses the configuration specified in there.

### BEGIN INIT INFO
# Provides:             cgconfig
# Required-Start:
# Required-Stop:
# Should-Start:
# Should-Stop:
# Short-Description:    start and stop the WLM configuration
# Description:          This script allows us to create a default configuration
### END INIT INFO

PATH=/bin:/usr/bin:/sbin:/usr/sbin:.
MOUNTS_FILE=/proc/mounts
PROC_CGROUPS_FILE=/proc/cgroups
CGROUP_FS=cgroup
CONFIG_FILE=/etc/cgconfig.conf

# support multiple mount points
declare -a MOUNTPOINT
declare -a MOUNTOPTS
maxindex=0
servicename=cgconfig

#
# Source LSB routines
#
. /lib/lsb/init-functions

parse_mounts() {
    while read name mountpt fs opts other
    do
        if echo $name | grep -q $CGROUP_FS
        then
            maxindex=$(($maxindex+1))
            MOUNTPOINT[$maxindex]=$mountpt
            MOUNTOPTS[$maxindex]=$opts
        fi
    done < $MOUNTS_FILE

    return 0;
}

umount_fs() {
        for i in `seq 1 $maxindex`
        do
                umount ${MOUNTPOINT[$i]}
                rmdir ${MOUNTPOINT[$i]}
        done
}

start() {
	if [ -f /var/lock/subsys/$servicename ]
        then
            log_warning_msg "lock file already exists"
            return
        fi

        if [ $? -eq 0 ]
        then
                #log_progress_msg "Starting cgconfig service: "
                cgconfigparser -l $CONFIG_FILE
                retval=$?
                if [ $retval -ne 0 ]
                then
                    return $retval
                fi
        fi

        declare defaultcgroup

        if [ -f /etc/cgrules.conf ]
        then
            read user ctrl defaultcgroup <<< \
                `grep -m1 ^\* /etc/cgrules.conf`
            if [[ -n $defaultcgroup && $defaultcgroup = "*" ]]
            then
                log_warning_msg "/etc/cgrules.conf incorrect"
                log_warning_msg "Overriding it"
                defaultcgroup=
            fi
        fi

        if [ -z $defaultcgroup ]
        then
            defaultcgroup=sysdefault/
        fi
        #
        # Create a default class for tasks to return back to
        #
        parse_mounts
        for i in `seq 1 $maxindex`
        do
            #
            # Ignore if directory already exists
            #
            mkdir ${MOUNTPOINT[$i]}/$defaultcgroup 2> /dev/null
            chmod a+rw ${MOUNTPOINT[$i]}/$defaultcgroup/tasks
            #
            # special rule for cpusets
            #
            echo ${MOUNTOPTS[$i]} | grep -q -w cpuset
            if [ $? -eq 0 ]
            then
                cat ${MOUNTPOINT[$i]}/cpuset.cpus > \
                    ${MOUNTPOINT[$i]}/$defaultcgroup/cpuset.cpus
                cat ${MOUNTPOINT[$i]}/cpuset.mems > \
                    ${MOUNTPOINT[$i]}/$defaultcgroup/cpuset.mems
            fi
            #
            # classify everything to default cgroup
            #
            for j in `ps --no-headers -eL o tid`
            do
                echo $j > ${MOUNTPOINT[$i]}/$defaultcgroup/tasks 2>/dev/null
            done
        done
	
        touch /var/lock/subsys/$servicename
        return $?
}

move_all_to_init_class() {
    for i in `seq 1 $maxindex`
    do
        cd ${MOUNTPOINT[$i]}
        cat /proc/mounts | grep -wq ${MOUNTPOINT[$i]}
        if [ $? -ne 0 ]
        then
            log_failure_msg "resource control filesystem not mounted"
            exit 1
        fi

        for i in `find . -depth -type d`
        do
            case $i in
            '.')
                ;;
            *)
                class=${i#./*}
                #log_progress_msg "Removing class $class"
                sed -nu p < ./$i/tasks > tasks
                rmdir $i
                ;;
            esac
        done
        cd - > /dev/null
    done
}


stop() {
    move_all_to_init_class
    umount_fs
    rm -f /var/lock/subsys/$servicename
}

trapped() {
    #
    # Do nothing
    #
    true
}

usage() {
    echo "$0 <start|stop|restart|condrestart|status>"
    exit 1
}

common() {
    #
    # main script work done here
    #
    trap "trapped ABRT" ABRT
    trap "trapped QUIT" QUIT
    trap "trapped TERM" TERM
    trap "trapped INT"   INT

    parse_mounts
}

case $1 in
    'stop')
        common
        stop;
        ;;
    'start')
        common
        start;
        ;;
    'restart')
        common
	stop
        start
        ;;
    'reload')
        common
	stop
        start
        ;;
    'condrestart')
        if [ -f /var/lock/subsys/$servicename ] ; then
            stop
            start
        fi
        ;;
    'status')
        if [ -f /var/lock/subsys/$servicename ] ; then
            echo "Running"
        else
            echo "Stopped"
        fi
	;;
    *)
        usage
        ;;
esac