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Date: Thu, 22 Jan 2009 13:03:37 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
       Frederic Weisbecker <fweisbec@gmail.com>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [PATCH 1/5] trace: do not disable wake up tracer on output of
	trace
Message-ID: <20090122120337.GB22594@elte.hu>
References: <20090121235306.224764198@goodmis.org> <20090121235805.771064570@goodmis.org> <20090122084105.GD7438@elte.hu> <alpine.DEB.1.10.0901220658050.22776@gandalf.stny.rr.com>
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* Steven Rostedt <rostedt@goodmis.org> wrote:

> Well actually, I don't see the output causing any issues. That's another 
> point. Should we work on adding all this complex code for something that 
> might not every cause an issues?  I added it because it did cause an 
> issue with the irqs off traces, although I'm not sure that is true any 
> more either. I just added it to the wakeup tracer just to be consistent.
> 
> With the new trace_off switch that disables the ring buffer, and the 
> stopping of the swap buffers with the switch off, I do not think that 
> this code is even necessary anymore.
> 
> I think I'll rip out the code from irqsoff and see if it is still an 
> issue there. If not, I think we can get rid of it.

agreed - if the output itself does not disturb max-latency tracing in 
practice then i'm all for ripping it out.

	Ingo