lkml.org 
[lkml]   [2008]   [Jul]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: 2.6.24-rc8-rt1: Strange latencies on mpc5200 powerpc - RCU issue?
Steven Rostedt wrote:
> On Wed, 2 Jul 2008, Wolfgang Grandegger wrote:
>
>> Steven Rostedt wrote:
>>> On Tue, 1 Jul 2008, Wolfgang Grandegger wrote:
>>>> I continue this thread because it's still not understood why enabling
>>>> CONFIG_RCU_TRACE is necessary to get reasonable latencies on the
>>>> MPC5200. It might also explain, why I get much worse latencies with
>>>> 2.6.25.8-rt7.
>>> Have you tried turning on ftrace?
>> Hm, is it available for PowerPC? I have not found yet how to enable it.
>
> Hmm, should be. But I need to test it on my PPC box first before I can
> tell you for sure. If you don't see a way to enable it, perhaps I haven't
> updated the config options for PPC yet.

I added HAVE_FTRACE and HAVE_DYNAMIC_FTRACE to "config PPC" but more
seems to be missing, e.g. arch/powerpc/kernel/ftrace.c. Nevertheless,
how would I trigger high latency events with ftrace. I there a
description somewhere?

Wolfgang.



\
 
 \ /
  Last update: 2008-07-06 11:37    [from the cache]
©2003-2011 Jasper Spaans