From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: Measuring worst case interrupt processing time
Date: Sun, 08 Dec 2013 19:49:44 -0800
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	(Mohammed Riyaz's message of "Sun, 8 Dec 2013 05:18:06 -0800")
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To: Mohammed Riyaz <riyaz.list@gmail.com>
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Mohammed Riyaz <riyaz.list@gmail.com> writes:

> Hi,
>
> I am working on trying to measure the worst case processing time for
> hard IRQ and soft IRQ. Well, I understand that we could use time
> stamps at entry and exit to measure this. Just wanted to know if there
> were other standard ways of measuring this. Any suggestions?

If your goal is to identify worst case latencies of interrupted code --
ftrace has special tracers for this: CONFIG_{IRQSOFF,PREEMPT,SCHED}_TRACER

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only