Hi Wolfgang, Wolfgang Grandegger wrote: > Hi Fun, What's so funny? ;-) [...] > But as Steven pointed out, the preempt_enable_noresched at that place > might be illegal, anyway. In 2.6.25-rt, trace_mark() is no longer > used and I do not see an improvement with CONFIG_RCU_TRAC any more. > Latencies go up to 600us. I also tried with CONFIG_RCU_BOOST > disabled, but it did not improve the latencies. Actually, I still > measure significantly different latencies with 2.6.24.4-rt4, > 2.6.24.7-rt14 and 2.6.25.8-rt7, which is quite frustrating. As you > seem not be able to reproduce my high latencies, I wonder if there > are some toolchain or glibc related issues. I took a quick look into the rcppreempt boost stuff in 2.6.24-rt and 2.6.25-rt. As you have mentioned, trace_mark is no more used in 2.6.24-rt. Instead of that flags are used to detect if the task is preempted. It might indeed probably be some toolchain issue. My powerpc toolchain I'm using here contains gcc 4.1.2 and glibc 2.5 Cheers Fu (without n) -- Dipl.-Ing. Luotao Fu | Phone: +49-5121-206917-3 Pengutronix - Linux Solutions for Science and Industry Entwicklungszentrum Nord http://www.pengutronix.de -- 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
