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Subject: Re: [PATCH] new irq tracer
From: Peter Zijlstra <peterz@infradead.org>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org>,
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Date: Fri, 27 Feb 2009 08:25:32 +0100
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On Fri, 2009-02-27 at 12:33 +0900, KOSAKI Motohiro wrote:
> 
> I agree with IRQ latency tracing is very important.

Then use the irq-latency tracer, that thing is specifically created to
measure and locate irq-off latency sources.

We've been using it for years in the preempt-rt patch-set.