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Date: Tue, 30 Sep 2008 00:01:55 -0700 (PDT)
From: Parav Pandit <paravpandit@yahoo.com>
Reply-To: paravpandit@yahoo.com
Subject: Calculating time in order of 0.1usec on x86 system
To: Linux kernel <linux-kernel@vger.kernel.org>
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Hi,

I need to calculate time spent by a function in order of less then a microsecond on x86 SMP platform.

Current profiling tools and gettimeofday() are not sufficient.

So I am using get_cycles() to get the CPU cycles.

Now how do I convert it into the time interval?

Do I have to divide it by "cpu_khz" variable? Or some other method?
Is yes, what will be the unit of the result (time interval)? nsec/usec/msec?

e.g. get_cycles()/cpu_khz (unit?)

Or Is there more simpler method exist?

Regards,
Parav Pandit