From owner-freebsd-alpha  Sun Apr 29  8:46:37 2001
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To: freebsd-alpha@FreeBSD.ORG
Subject: determine cycle counter frequency in user space
From: Rolf Neugebauer <neugebar@dcs.gla.ac.uk>
Date: 29 Apr 2001 16:46:24 +0100
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Hi,

I try to determine the cycle counter frequency from a user space
program to do some accurate time counting. Ideally, I would like to
access the rpb_cc_freq field Hardware Restart Parameter Block (rpb) as
possible under OSF/1 using getsysinfo(2) or the calibrated
cycles_per_sec variable from sys/alpha/alpha/machdep.c.

While it would be easy to introduce a new sysctl or similar, I was
wondering if there is already a 'standard' way under FreeBSD to access
this information (ideally, also under ix86).

I searched around a bit, but couldn't find any obvious way.

Thanks
Rolf

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