On Wed, 27 Mar 2013, Koehrer Mathias (ETAS/ESS2) wrote: > > > > Perhaps you might want to have a look at this thread, about RCU stalls > > and a possible common root cause for some of them. > > > > http://marc.info/?l=linux-rt-users&m=136258510132233&w=2 > > Thanks for the information. However the application is intended to > run with 100% CPU (real time) load on one core. That's why the CPU > core is isolated for. They are reserved for this application. Sure, but it's not possible today to run 100% CPU in user space. RCU is one of the issues, which has a solution in 3.8. See https://lwn.net/Articles/522262/ There is work in progress to solve the other issues as well, but that's not going to happen before 3.10. > The one option is to raise the prioriy of ksoftirq (which contains > the RCU stuff (if I know right...)) or I was playing with the > RCU_BOOST feature which I expected to have the same effect. RCU_BOOST does not solve that. It's about starvation of readside critical sections. See https://lwn.net/Articles/220677/ > However, the RCU_BOOST feature is not clear to me as I still saw the > kernel messages about RCU stalls that I did not want to see > anymore... Sure, RCU_BOOST is tackling a different problem. The callback free CPUs implementation is what you are looking for. Thanks, tglx -- 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
