From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfgang Grandegger <wg@grandegger.com>
Subject: Re: 2.6.24-rc8-rt1: Strange latencies on mpc5200 powerpc - RCU issue?
Date: Wed, 02 Jul 2008 10:09:35 +0200
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Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Luotao Fu <l.fu@pengutronix.de>,
	LKML <linux-kernel@vger.kernel.org>,
	RT <linux-rt-users@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Thomas Gleixner <tglx@linutronix.de>
To: Steven Rostedt <rostedt@goodmis.org>
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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.

Wolfgang.