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Message-ID: <454295F4.1050001@superbug.co.uk>
Date: Sat, 28 Oct 2006 00:27:48 +0100
From: James Courtier-Dutton <James@superbug.co.uk>
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To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Latency measurements
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Hi,

If I have an application using poll() to wait for an event, and that 
event it triggered by an interrupt handling routine in the kernel. E.g. 
DMA transaction completed. Is there any way for me to measure the 
latency between the kernel interrupt, and my application returning from 
the poll() call?

James