* Nicholas Mc Guire | 2013-12-27 21:00:24 [+0100]: >> - A patch from Thomas Gleixner not to raise the timer softirq >> unconditionally (only if a timer is pending) >> > >This one seems to deadlock early in the boot sequence on x86 >(i3/i7/Phenom-4x here and Carsten Emde also had boot failures) > >after droping this patch with: >patch -p1 -R < ../paches/timers-do-not-raise-softirq-unconditionally.patch >3.12.6-rt9 boots up fine. cyclictest seems to be back to what it was before >(only ran for a few minutes idle and 1h with load on an i3). > >The main problem with this patch though are proceduaral isues >the commit note - which is a mail exchange - actually does not explain what >the rational for the changes is (...well I don't understand the logic of >run_local_timers - if someone can explain - pleas do) and notably: > >from timers-do-not-raise-softirq-unconditionally.patch ><snip> >well, that very same problem is in mainline if you add "threadirqs" to >the command line. But we can be smart about this. The untested patch > ^^^^^^^^^^^^^^^^^^ >below should address that issue. If that works on mainline we can >adapt it for RT (needs a trylock(&base->lock) there). ><snip> > > does make me wonder why this went into -rt9 ? It was on the mailing list for a few weeks. My understanding was that Mike Galbraith tested it on mainline and then I added the RT specific pieces and added it it to the tree. > It also build fails with CONFIG_PREEMPT_RT_FULL not set. I will add a non-RT based config to my compile tests. > as with this patch, systems that booted just fine with 3.12.5-rt7 don't > even boot (atleast my 3 x86 test boxes here did not) this raises some > questions regarding the process of getting patches into -rtX - are > we going to fast here ? > > I would prefere if such patches would go out with a request for testing > or atleast a "might blow up your system" note in them... I didn't expect that much trouble. In general I try to avoid adding explosives unless marked as such. >thx! >hofrat Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
