Re: gettimeofday() & the commpage
Re: gettimeofday() & the commpage
- Subject: Re: gettimeofday() & the commpage
- From: Ed Wynne <email@hidden>
- Date: Fri, 30 Jul 2004 16:48:16 -0400
On Jul 30, 2004, at 4:16 PM, Andrew Gallatin wrote:
So.. how the heck do you do it? Is the actual clock hardware mapped
out to userspace? Or is there a trick I'm missing.
It uses the PowerPC timebase registers which are accessible from
userland. They count some multiple of the external bus frequency, as
long as you know the conversation factor, its somewhat trivial (and
very fast) to convert to wall clock time units.
-Ed
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