On 12/18/2014 9:40 AM, Hesham Moustafa wrote: > On Thu, Dec 18, 2014 at 3:38 PM, Joel Sherrill > <joel.sherr...@oarcorp.com> wrote: >> >> On December 18, 2014 5:18:31 AM PST, Sebastian Huber >> <sebastian.hu...@embedded-brains.de> wrote: >>> Hello, >>> >>> I work currently on concepts to implement mutex objects with SMP aware >>> locking protocols. Currently this is MrsP [1] and OMIP [2]. The >>> implementation should use fine grained locking. It turned out that the >>> >>> support for timeout makes the implementations much more complicated. >>> With timeouts you can tear a resource dependency tree into two >>> sub-trees >>> at arbitrary positions and this makes traversal difficult (you can cut >>> off the way back). >>> >>> Is there a valid use case for a mutex obtain operation with a timeout >>> in >>> case the locking protocol aims to provide bounded wait times? We can >>> probably also assume that the critical section has a bounded execution >>> time. >> I don't know if there is or not. It is close to Christmas but I can try to >> email Burns and Wellings. I have met them both a few times and they gave >> usually been quick to answer. >> >> Or we could send Hesham to their office hours .. Lol >> > Before I read this, I was about to reply that I can contact them faster :)
Please do and if you want to bring Sebastian and/or myself in, feel free to set up a Google Hangout. Say hi to them for me. :) >>> [1] A. Burns , A. J. Wellings, A Schedulability Compatible >>> Multiprocessor Resource Sharing Protocol -- MrsP, Proceedings of the >>> 2013 25th Euromicro Conference on Real-Time Systems, p.282-291, July >>> 09-12, 2013 >>> >>> [2] Björn B. Brandenburg, A Fully Preemptive Multiprocessor Semaphore >>> Protocol for Latency-Sensitive Real-Time Applications, Proceedings of >>> the 2013 25th Euromicro Conference on Real-Time Systems, p.292-302, >>> July >>> 09-12, 2013 >>> >>> -- >>> Sebastian Huber, embedded brains GmbH >>> >>> Address : Dornierstr. 4, D-82178 Puchheim, Germany >>> Phone : +49 89 189 47 41-16 >>> Fax : +49 89 189 47 41-09 >>> E-Mail : sebastian.hu...@embedded-brains.de >>> PGP : Public key available on request. >>> >>> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG. >>> >>> _______________________________________________ >>> devel mailing list >>> devel@rtems.org >>> http://lists.rtems.org/mailman/listinfo/devel >> --joel >> _______________________________________________ >> devel mailing list >> devel@rtems.org >> http://lists.rtems.org/mailman/listinfo/devel -- Joel Sherrill, Ph.D. Director of Research & Development joel.sherr...@oarcorp.com On-Line Applications Research Ask me about RTEMS: a free RTOS Huntsville AL 35805 Support Available (256) 722-9985 _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
