cgroups: major update to cgroups support

This reworks cgroups support so we have one variable in rc.conf for each
controller instead of each setting.

Also we add support for all of the possible cgroup controllers.

I would like to thank Alexander Vershilov for his help with testing and
reworking this code.

sh/rc-cgroup.sh.in

@@ -15,45 +15,74 @@ cgroup_find_path()
 	echo $result
 }
 
-# prepare values to be attached inside cgroups
-cgroup_prepare()
+cgroup_set_values()
 {
-	local h=$(cgroup_find_path "$1")
+	[ -n "$1" -a -n "$2" -a -d "/sys/fs/cgroup/$1" ] || return 0
+
+	local controller="$1" h=$(cgroup_find_path "$1")
 	cgroup="/sys/fs/cgroup/${1}${h}openrc_${RC_SVCNAME}"
-	[ -d ${cgroup} ] || mkdir -p ${cgroup}
-	return 0
-}
+	[ -d "$cgroup" ] || mkdir -p "$cgroup"
 
-cgroup_set_value()
-{
-	[ -f "$cgroup/${1}" -a -n "$2" ] && echo $2 > "${cgroup}/${1}"
-	return 0
-}
+	set -- $2
+	local name val
+	while [ -n "$1" -a "$controller" != "cpuacct" ]; do
+		case "$1" in
+			$controller.*)
+				if [ -n "$name" -a -f "$cgroup/$name" -a -n "$val" ]; then
+					veinfo "$RC_SVCNAME: Setting $cgroup/$name to $val"
+					echo $val > "$cgroup/$name"
+				fi
+				name=$1
+				val=
+				;;
+			*)
+				val="$val $1"
+				;;
+		esac
+		shift
+	done
+	if [ -n "$name" -a -f "$cgroup/$name" -a -n "$val" ]; then
+		veinfo "$RC_SVCNAME: Setting $cgroup/$name to $val"
+		echo $val > "$cgroup/$name"
+	fi
+
+	if [ -f "$cgroup/tasks" ]; then
+		veinfo "$RC_SVCNAME: adding to $cgroup/tasks"
+		echo 0 > "$cgroup/tasks"
+	fi
 
-cgroup_add_process()
-{
-	[ -f "${cgroup}"/tasks ] && echo 0 > "${cgroup}"/tasks
 	return 0
 }
 
 cgroup_set_limits()
 {
 	openrc_cgroup=/sys/fs/cgroup/openrc
-	if [ -d ${openrc_cgroup} ]; then
-		cgroup=${openrc_cgroup}/${RC_SVCNAME}
-		mkdir -p ${cgroup}
-		[ -f "${cgroup}"/tasks ] && echo 0 > "${cgroup}"/tasks
+	if [ -d "$openrc_cgroup" ]; then
+		cgroup="$openrc_cgroup/$RC_SVCNAME"
+		mkdir -p "$cgroup"
+		[ -f "$cgroup/tasks" ] && echo 0 > "$cgroup/tasks"
 	fi
 
-	if [ -d /sys/fs/cgroup/cpu ]; then
-		local share
+	local blkio="${rc_cgroup_blkio:-$RC_CGROUP_BLKIO}"
+	[ -n "$blkio" ] && cgroup_set_values blkio "$blkio"
+
+	local cpu="${rc_cgroup_cpu:-$RC_CGROUP_CPU}"
+	[ -n "$cpu" ] && cgroup_set_values cpu "$cpu"
+
+	local cpuacct="${rc_cgroup_cpuacct:-$RC_CGROUP_CPUACCT}"
+	[ -n "$cpuacct" ] && cgroup_set_values cpuacct "$cpuacct"
+
+	local cpuset="${rc_cgroup_cpuset:-$RC_CGROUP_cpuset}"
+	[ -n "$cpuset" ] && cgroup_set_values cpuset "$cpuset"
+
+	local devices="${rc_cgroup_devices:-$RC_CGROUP_DEVICES}"
+	[ -n "$devices" ] && cgroup_set_values devices "$devices"
+
+	local memory="${rc_cgroup_memory:-$RC_CGROUP_MEMORY}"
+	[ -n "$memory" ] && cgroup_set_values memory "$memory"
+
+	local net_prio="${rc_cgroup_net_prio:-$RC_CGROUP_NET_PRIO}"
+	[ -n "$net_prio" ] && cgroup_set_values net_prio "$net_prio"
 
-		share=${rc_cgroup_cpu_shares:-$RC_CGROUP_CPU_SHARES}
-		if [ -n "$share" ]; then
-			cgroup_prepare "cpu"
-		cgroup_set_value "cpu.shares" $share
-			cgroup_add_process
-		fi
-	fi
 	return 0
 }