RFR: JDK-8073057 JDK-8073058

[alexey karaksin]

the root cause is that the files into gpioN directory become accessible 
for writing after udev script changed their permissions.
this may take 130 milliseconds on RPi board and more on slower boards.
have done tests on RPI.

updated the diff files http://cr.openjdk.java.net/~amironov/8073057.1/


On 13.02.2015 10:29, alexey karaksin wrote:
>
> issues:
> https://bugs.openjdk.java.net/browse/JDK-8073058 DNF for pin that was 
> exported previously
> https://bugs.openjdk.java.net/browse/JDK-8073057 Add wait procedure 
> after GPIO export
>
> webrev: http://cr.openjdk.java.net/~amironov/8073057/
>
> 1. In the GPIO Pin open procedure added check if file 
> /sys/class/gpio/gpioN/direction exists, if so, no necessary write pinn 
> number to the export file.
> 2. added usleeps between attempts to open write to the export file and 
> open /sys/class/gpio/gpioN/direction. usleep is because neither 
> "inotify" nor fanotify handle sysfs gpioN directory creation properly.