# source these in to your shell to simplify working with
# mmtrace debugfs controls...
# ==========================================================
# mmtrace wrappers

function hex  { printf "0x%lx\n" "$1" ; }

_DEBUGFS=/sys/kernel/debug
## __mmt [{-V|-X}] <var> [<newval>]
__mmt()
{
	typeset value_only=false
	typeset decval=true
	while [[ "${1#-}" != "$1" ]]; do
		case "$1" in
		-V)	value_only=true
			shift
			;;
		-X)	decval=false	# i.e., hex
			shift
			;;
		esac
	done

	typeset var=mmtrace/$1
	typeset vfile=$_DEBUGFS/$var
	if [[ ! -f $vfile ]]; then
	    echo "No such control:  $1" >&2
	    return 4
	fi

	typeset oldval=$( cat $vfile )
	$decval || oldval=$( hex $oldval )
	typeset newval="$2"
	if [[ -n "$newval" ]]; then
		echo "setting $var to $newval:" >&2
		/bin/echo -E "$newval" >$vfile
		typeset result=$( cat $vfile )
		$decval || result=$( hex $result )
		echo -e "\t$oldval => $result" >&2
	else
		if $value_only; then
			echo "$oldval"
		else
			echo -e "\t$var = $oldval"
		fi
	fi
}

__show_mmtrace_mask()
{
	typeset val=$( __mmt -V -s $1 mask)
	echo "mmtrace: $1/mask = $(hex $val)"
}
mmt()
{
	typeset what="$1"
	typeset val="$2"

	case "$what" in
	create)
		__mmt create 1
		;;
	destroy)
		__mmt create 0
		;;
	on|enable)
		__mmt enable 1
		;;
	off|disable)
		__mmt enable 0
		;;
	mask)
		__mmt -X mask $val
		;;
	uid)
		__mmt uid $val
		;;
	pid)
		__mmt pid $val
		;;
	subbuf_size)
		__mmt subbuf_size $val
		;;
	nr_subbufs)
		__mmt nr_subbufs $val
		;;
	state)
		__mmt create
		__mmt enable
		__mmt uid
		__mmt pid
		__mmt -X mask
		__mmt subbuf_size
		__mmt nr_subbufs
		;;
	*)
		echo "mmt {state|create|destroy|on|enable|off|disable|mask [<value>]"
		echo "     |uid [<value>]|pid [<value>]|subbuf_size <KB>|nr_subbufs <#>}"
		;;
	esac
}

lsmmt()
{
	typeset lsopts=
	while [[ "${1#-}" != "$1" ]]; do
		lsopts="$lsopts $1"
		shift
	done

	ls $lsopts $_DEBUGFS/mmtrace/$1
}