#!/bin/bash
#
#   Copyright(c) 2013-2016, Wind River Systems, Inc. 
#
#   Redistribution and use in source and binary forms, with or without
#   modification, are permitted provided that the following conditions
#   are met:
#
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#

# Query the metadata server for the set of cpus that are supposed to be offline
# It will be in the form "set([])" for the empty set, and "set([1, 2, 3])" for the
# non-empty set.
CPUSET_OFFLINE=`wget -t 3 -T 5 -qO - http://169.254.169.254/latest/meta-data/offline_cpuset`
RC=$?
if [ $RC -ne 0 ]
then
    logger -p daemon.err "${0}: unable to obtain "offline_cpuset" value.  rc: ${RC}"
    exit -1
fi

OFFLINE_CPUS=`echo ${CPUSET_OFFLINE}|grep -oE [0-9]+`
for CPU in $OFFLINE_CPUS
do
    # Offline this cpu to match the underlying virtual machine.
    echo 0 > /sys/devices/system/cpu/cpu${CPU}/online
    RC=$?
    if [ $RC -ne 0 ]
    then
        logger -p daemon.err "${0}: unable to offline cpu ${CPU}.  rc: ${RC}"
        exit -1
    fi
done