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Date: Wed, 12 Sep 2012 10:57:28 -0400
From: Jon Masters <jcm@redhat.com>
Organization: Red Hat, Inc.
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To: Steven Rostedt <rostedt@goodmis.org>
CC: LKML <linux-kernel@vger.kernel.org>, RT <linux-rt-users@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Darren Hart <dvhart@linux.intel.com>,
        Clark Williams <clark@redhat.com>
Subject: Re: [PATCH RT] hwlat_detector: Check the outer side of the loop
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On 09/12/2012 10:34 AM, Steven Rostedt wrote:
> The hwlat_detector performs the following test:
>
> 	t1 = ktime_get();
> 	t2 = ktime_get();
>
> 	[ do the checks of t2 - t1 ]
>
> It can detect things like SMIs if it occurs between the t1 and t2
> timestamps, as there will be a large difference between the two.

Oops. Good catch.

Jon.