john cooper wrote: > The more daunting problem stems from limitations in the MIPS > ABI which makes the latency trace support problematic. > Rather than rehash the issue: > > http://lists.linuxcoding.com/kernel/2005-q4/msg10163.html > > Until we have a usable instrumentation solution in place, > characterization, debug, and support of PREEMPT_RT for MIPS > is going to be a challenge.
Agreed. I have been using KFT (Kernel Function Trace) on MIPS, and it has decent support for function traceback reporting, but it's not currently integrated with latency-trace at all. We should discuss if this could possibly be used to debug RT-preempt. It is much heavier weight than the mcount stuff, but uses similar (but not identical) gcc profiling instrumentation. I'm not sure if the two can be turned on together, or how hard it would be to move latency-trace onto -finstrument_functions. But it's probably worth researching a little. We'll need something to give insight into the problem paths. -- Tim ============================= Tim Bird Architecture Group Chair, CE Linux Forum Senior Staff Engineer, Sony Corporation of America ============================= - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
