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Date: Tue, 19 Oct 2010 16:07:09 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Steven Rostedt <rostedt@goodmis.org>
cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Koki Sanagi <sanagi.koki@jp.fujitsu.com>,
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Subject: Re: [PATCH] tracing: Cleanup the convoluted softirq tracepoints
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On Tue, 19 Oct 2010, Steven Rostedt wrote:

> On Tue, 2010-10-19 at 15:41 +0200, Thomas Gleixner wrote:
> > On Tue, 19 Oct 2010, Mathieu Desnoyers wrote:
> 
> > Dudes, a vector computation is hardly a performance problem in that
> > function and definitely not an excuse for designing such horrible
> > interfaces.
> 
> Yes, now we can be a bit more liberal. But when these tracepoints were
> going in, people were watching to make sure they have practically zero
> impact when tracing was disabled.
> 
> Now that people are more use to tracepoints, they are more understanding
> to have cleaner code over that extra few more lines of machine code in
> the fast path.

The vector computation is compared to the extra tracing induced jumps
probably not even measurable. Stop defending horrible coding with
handwavy performance and impact arguments.

Thanks,

	tglx