[Pm-utils] [PATCH] unload modules recursively

[Stefan Seyfried]

On Thu, Oct 05, 2006 at 06:05:46PM +0200, Stefan Seyfried wrote:
> Hi.
> 
> Sometimes it is usefull to unload a complete stack of modules.
> This patch implements that:
> 
> Index: pm/functions
> ===================================================================
> RCS file: /cvs/pm-utils/pm-utils/pm/functions,v
> retrieving revision 1.20
> diff -u -p -r1.20 functions
> --- pm/functions	28 Sep 2006 21:25:36 -0000	1.20
> +++ pm/functions	5 Oct 2006 16:00:39 -0000
> @@ -113,13 +113,46 @@ pm_main()
>  	return 0
>  }
>  
> +# this recursively unloads the given modules and all that depend on it
> +# first parameter is the module to be unloaded
>  modunload()
>  {
> -	/sbin/lsmod 2>/dev/null | grep -q "$1"
> -	if [ "$?" == "0" ]; then
> -		echo "export ${1}_MODULE_LOAD=yes" >> /var/run/pm-suspend
> -		/sbin/modprobe -r "$1" >/dev/null 2>&1
> -	fi
> +	local MOD D C USED MODS I
> +	local UNL=$1 RET=1
> +	# RET is the return code. If at least one module was unloaded, return 0.
> +	#     if the module was not loaded, also return 0 since this is no error.
> +	#     if no module was unloaded successfully, return 1
> +	while read MOD D C USED D; do
> +		[ "$MOD" != "$UNL" ] && continue
> +		if [ "$USED" == "-" ]; then
> +			if [ $C -eq 0 ]; then
> +				if rmmod $UNL; then
> +					echo "export ${UNL}_MODULE_LOAD=yes" >> /var/run/pm-suspend
> +					RET=0
> +				else
> +					echo "## could not unload '$UNL', usage count was 0" \
> +						>> /var/run/pm-suspend
> +				fi
> +			else
> +				echo "## could not unload '$UNL', usage count: $C" >> \
> +					/var/run/pm-suspend
> +			fi
> +		else
> +			USED=${USED//,/ }
> +			MODS=($USED)
> +			# it seems slightly more likely to rmmod in one pass, if we try backwards.
> +			for I in `seq $[${#MODS[@]}-1] -1 0`; do
> +				MOD=${MODS[$I]}
> +				modunload $MOD && RET=0
> +			done
> +			# if we unloaded at least one module, then let's try again!
> +			[ $RET -eq 0 ] && modunload $UNL
> +			RET=$?
> +		fi
> +		return $RET
> +	done < /proc/modules
> +	# if we came this far, there was nothing to do, the module is no longer loaded.
> +	return 0
>  }
>  
>  modreload()


ok, this might actually unload more modules than it will be reloading during
resume. How about:

    if rmmod $UNL; then
        echo "export RESUME_MODULES=\"$UNL \$RESUME_MODULES\"" >> /var/pm/pm-suspend
        RET=0
    else

.....

and then use RESUME_MODULES in 50modules like this:

resume_modules()
{
	for x in $RESUME_MODULES; do
		modprobe $x > /dev/null 2>&1
	done
}
-- 
Stefan Seyfried
QA / R&D Team Mobile Devices        |              "Any ideas, John?"
SUSE LINUX Products GmbH, Nürnberg  | "Well, surrounding them's out."