Hi, On 03.12.2009, at 14:14, Gilles Chanteperdrix <gilles.chanteperd...@xenomai.org > wrote:
> Wolfgang Mauerer wrote: >> Hi, >> >> Gilles Chanteperdrix wrote: >>> Wolfgang Mauerer wrote: >> >>>> So that means, in essence, that you would accept probabilistic >>>> algorithms in realtime context? >>> Ah, today's troll! >> >> though it seems that I have to replace Jan this time ;-) >>> As I think I explained, the use of a seqlock in real-time context >>> when >>> the seqlock writer only happens in linux context is not >>> probabilistic. >>> It will work every time the first pass. >> >> I still don't see why it should succeed every time: What about >> the case that the Linux kernel on CPU0 updates the data, while >> Xenomai accesses them on another CPU? This can lead to >> inconsistent data, and they must be reread on the Xenomai side. > > Yeah, right. I was not thinking about SMP. But admit that in this > case, > there will be only one retry, there is nothing pathological. > >> >> I'm asking because if this case can not happen, then there's >> nothing left to to as I have the code already at hand. > > You have reworked the nucleus timers handling to adapt to this new > real-time clock ? Nope. Sorry, I was a bit unclear: I'm just referring to the gtod syscall that does the timer handling, Not any other adaptions. Thanks, Wolfgang _______________________________________________ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
