#!/bin/bash

prepare() {
    systemctl start vm-usb-helper

    echo "Defrag RAM"
    echo 1 > /proc/sys/vm/compact_memory
    for _ in $(seq 5); do
        sleep 3
        # assign hugepages
        sysctl -w vm.nr_hugepages=8192 && break
    done
    sleep 10

    echo "Setup cpuset cgroup for host"
    sudo cset set -c 0,4 -s system
    sudo cset proc -m -f root -t system
    sudo cset proc -k -f root -t system --force

    echo "Setup cpumask"
    for i in /sys/devices/virtual/workqueue/*/cpumask; do
        sudo sh -c "echo 001 > $i"
    done;

    echo "Setup interrupt affinity"
    for i in $(sed -n -e 's/ \([0-9]\+\):.*vfio.*/\1/p' /proc/interrupts); do
        sudo sh -c "echo 0,4 > /proc/irq/$i/smp_affinity_list"
    done

    echo "Set the CPU frequency governor to performance"
    for f in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do
        echo performance >$f
    done
}

release() {
    echo "Restore system"
    # irq
    for i in $(sed -n -e 's/ \([0-9]\+\):.*vfio.*/\1/p' /proc/interrupts); do
        sudo sh -c "echo ff > /proc/irq/$i/smp_affinity"
    done
    # cpumask
    for i in /sys/devices/virtual/workqueue/*/cpumask; do
        sudo sh -c "echo ff > $i"
    done;
    # cpuset
    sudo cset set -d system &>/dev/null

    for f in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do
        echo powersave >$f
    done

    systemctl stop vm-usb-helper
    sysctl -w vm.nr_hugepages=0
}

if [ "$1" == "win10" ]; then
    if [ "$2" == "prepare" ]; then
        prepare
    fi
    if [ "$2" == "release" ]; then
        release
    fi
fi