From owner-freebsd-smp  Sun Apr  5 05:12:24 1998
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	Sun, 5 Apr 1998 22:09:39 +1000
Date: Sun, 5 Apr 1998 22:09:39 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199804051209.WAA03352@godzilla.zeta.org.au>
To: bde@zeta.org.au, phk@critter.freebsd.dk
Subject: Re: more SMP stuff
Cc: peter@netplex.com.au, smp@FreeBSD.ORG
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>>I found the bug in microtime():
>>(1) the dummy timecounter has a frequency of only 10^5 Hz, but it runs
>>    much faster than that so we get too-large delta counts.
>
>Ups, I intended that to be 10^6 Hz...

The scaling needs to be more robust since the h/w counter might be
slower than 10^6 hz.

>This isn't it anyway, the dummy counter is only used by syscons 
>screensaver calls to getmicroruntime();

It's used by my version of the floppy driver which calls microtime()
to timestamp certain events.

I don't think I call nanotime() so early.  My rtcintr() calls
nanotime() to gather statistics, and nanotime() was reentered.
I don't see any reentrancy problems.  There will be one when
nanotime updates tc->nanotime like it should.

Bruce

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