Re: Accessing Pentium MSRs
Tomas Andersson (f91-tan@nada.kth.se)
Fri, 12 Apr 1996 08:25:43 +0200
Theodore Ts'o wrote:
> If I remember correctly, there's some way of enabling r/o access the
> time stamp counter from user mode. If that's true, then we don't have
> to use the syscall method at all. This would be a big win, since the
> syscall processing adds quite a large number of extra cycles to the time
> stamp counter. :-)
>
> - Ted
Forgive me if this has nothing to do with it, but, I was poking around the net and found
http://www.cs.utexas.edu/users/markj/zentimer.html which is a c++ class implementation of a
timer that make use of a pentium register, obviously in user mode. Might be worthwhile
having a look at.
/Tomas