gloomyandy wrote:Which isMoving always returns true? Pilot? Navigator, RegulatedMotor? Please add calls to all of them and let me know what each level returns. Also what listeners are not called, the ones in the Pilot, Navigator etc?
This is Porgy, Alan Turing's teddy bear. If any bear can help then this one should be able to!
"stuck" meant "call never returns".gloomyandy wrote:What do you mean by "stuck"
I confess not beeing a specialist of shared mem et al., so didn't really know which kind of system level mechanism is behind. I was just suspecting that reading from specific hardware addresses could trigger some low level process which could be the deep cause of the trouble. I could see this kind of mechanism when working with micro-controller and electronics based systems. But if you say there is nothing which can lock when reading from this kind of shared mem, I'll go and look elsewhere.gloomyandy wrote: it is hard to imagine how getTachoCount can stick since it simply returns a value from shared memory,
I've already added traces here and there, but there is still room for more. But as you know, adding traces modifies the execution timeline by adding delays, and thus this is not really neutral when tracking time related problems such as dead locks or concurrency. Hope this will not be one of these situations where the instrumentation "cures" the problem and makes it very difficult to track.gloomyandy wrote:a possibility is that there is some sort of deadlock can you get a stack trace when things stick?
I've tried removing some others but not yet this one. I'll give it a chance tonight.gloomyandy wrote:You could try removing the synchronized keyword from this line:
https://sourceforge.net/p/lejos/ev3/ci/ ... .java#l542
Very interesting, especially if the deadlock detection works as advertised.gloomyandy wrote:To get a stack trace if you are running your program from an ssh connection try typing ctrl+\ (control and backslash) this should trigger a stack trace. see:
http://www.oracle.com/technetwork/java/ ... html#gbmps
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