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Subject: Re: [RFC][PATCH] linux-2.5.59_getcycles_A0
From: john stultz <johnstul@us.ibm.com>
To: Andi Kleen <ak@suse.de>
Cc: lkml <linux-kernel@vger.kernel.org>, Joel Becker <Joel.Becker@oracle.com>
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On Fri, 2003-02-07 at 17:52, Andi Kleen wrote:
> > However this doesn't work on systems w/o a synced TSC, so by simply
> 
> Why not? This shouldn't be performance critical and you can make 
> it monotonous with an additional variable + lock if backwards jumps
> should be a problem.
> 

That sounds horrible! The extra locking and variable reading is going to
kill most of the performance concerns you have about reading an
alternate time source. 

I'm not sure I understand your resistance to using an alternate clock
for get_cycles(). Could you better explain your problem with it?

thanks
-john