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Date: Wed, 25 Feb 2009 11:09:28 -0500 (EST)
From: Steven Rostedt <rostedt@goodmis.org>
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To: Ingo Molnar <mingo@elte.hu>
cc: Andrew Morton <akpm@linux-foundation.org>,
       Pekka Enberg <penberg@cs.helsinki.fi>,
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       KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
       Jens Axboe <jens.axboe@oracle.com>,
       Masami Hiramatsu <mhiramat@redhat.com>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [PATCH 2/4] tracing: add event trace infrastructure
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On Wed, 25 Feb 2009, Ingo Molnar wrote:
> > Yeah, maybe that file (latency_trace) is a bit too much. I for 
> > one love it. It is great to load a kernel on some remote box, 
> > and run the irqs off latency tracer to see where the 
> > interrupts are disabled for the longest time. This format is 
> > really nice because it shows me when we are in an interrupt, 
> > or interrupts are disabled, and when the task should have been 
> > rescheduled.
> > 
> > This has help find places that we miss a preemption check too.
> 
> Could we get that, as PeterZ has suggested, as a trace_option 
> column in the 'trace' file? It would be default off for 
> non-latency tracers, with latency tracing plugins turning it on 
> by default. Would that work?

Sure, I'd be fine with it as an option. I just don't want to 
completely lose the ability to retrieve that information.

-- Steve