From mboxrd@z Thu Jan  1 00:00:00 1970
From: Suresh Kumar SHUKLA <suresh.shukla@st.com>
Subject: Measuring timer interrupt latency
Date: Mon, 13 Apr 2009 12:14:42 +0530
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Hi,

I want to profile the improvements in interrupt latency with and without RT
patches.

The approach I have in mind is that time gap between IRQ firing and IRQ
handler reading value of counter would be sufficient to reveal the interrupt
latency. These values can be analysed for min/max/avg.

Is there any test program which captures interrupt latency (for x86) ? 
I checked realfeel but it is user mode program and am not sure of its
accuracy.

regards,
Suresh