Reviewed-by: Michael Tremer <michael.tremer(a)ipfire.org>

This is an interesting approach to an interesting problem.

I guess it solves the problem well, although we should not be in the position where we have to build all this code :)

> On 25 Mar 2020, at 06:35, Arne Fitzenreiter <arne_f(a)ipfire.org> wrote:
> 
> on some machines the i2c sensor search take very long time
> which cause hang at first boot.
> 
> Now the search is started in background and waited for max one
> minute before continue load of collectd.
> On such machines collectd will not get all sensors at first startup.

Can scan_for_sensors() not simply check if collectd is already running and if so, simply restart it?

Best,
-Michael

> 
> fixes #12329
> 
> Signed-off-by: Arne Fitzenreiter <arne_f(a)ipfire.org>
> ---
> src/initscripts/system/collectd | 56 ++++++++++++++++++++++-----------
> 1 file changed, 37 insertions(+), 19 deletions(-)
> 
> diff --git a/src/initscripts/system/collectd b/src/initscripts/system/collectd
> index 5233525f0..20072780a 100644
> --- a/src/initscripts/system/collectd
> +++ b/src/initscripts/system/collectd
> @@ -6,6 +6,28 @@
> 
> eval $(/usr/local/bin/readhash /var/ipfire/main/settings)
> 
> +scan_for_sensors() {
> +	touch /var/lock/sensors_search
> +	# pre scan and try to load modules
> +	"yes" | /usr/sbin/sensors-detect > /dev/null
> +	if [ -e /etc/sysconfig/lm_sensors ]; then
> +
> +		# Module load
> +		. /etc/sysconfig/lm_sensors
> +		for modul in $BUS_MODULES $HWMON_MODULES ; do
> +			modprobe $modul > /dev/null 2>&1;
> +		done
> +	fi
> +
> +	# Final scan
> +	"yes" | /usr/sbin/sensors-detect > /dev/null
> +
> +	if [ ! -e /etc/sysconfig/lm_sensors ]; then
> +		echo "#No Sensors detected " > /etc/sysconfig/lm_sensors
> +	fi
> +	rm /var/lock/sensors_search
> +}
> +
> if [ "$RRDLOG" = '' ]; then
> 	RRDLOG=/var/log/rrd
> fi
> @@ -42,27 +64,23 @@ case "$1" in
> 
> 		# At first run search for sensors with sensors-detect
> 		if [ ! -e /etc/sysconfig/lm_sensors ]; then
> -			boot_mesg "Searching for Sensors..."
> -
> -			# pre scan and try to load modules
> -			"yes" | /usr/sbin/sensors-detect > /dev/null
> -			if [ -e /etc/sysconfig/lm_sensors ]; then
> -
> -				# Module load
> -				. /etc/sysconfig/lm_sensors
> -				for modul in $BUS_MODULES $HWMON_MODULES ; do
> -					modprobe $modul > /dev/null 2>&1;
> -				done
> -			fi
> -
> -			# Final scan
> -			"yes" | /usr/sbin/sensors-detect > /dev/null
> -			evaluate_retval
> +			# Don't run at next boot again
> +			touch /etc/sysconfig/lm_sensors
> +			boot_mesg -n "Searching for Sensors..."
> +			scan_for_sensors &
> +			sleep 2
> +		fi
> 
> -			if [ ! -e /etc/sysconfig/lm_sensors ]; then
> -				echo "#No Sensors detected " > /etc/sysconfig/lm_sensors
> -			fi
> +		if [ -e /var/lock/sensors_search ]; then
> +			for (( i=1; i<30; i++)) do
> +				if [ ! -e /var/lock/sensors_search ]; then
> +					break;
> +				fi
> +				boot_mesg -n "."
> +				sleep 2
> +			done
> 		fi
> +		boot_mesg ""
> 
> 		# Load sensor modules only first start
> 		if [ ! -e /var/lock/sensors_modules ]; then
> -- 
> 2.17.1
>