From: Con Kolivas <kernel@kolivas.org>
To: Daniel =?iso-8859-1?q?Marjam=E4ki?= <daniel.marjamaki@comhem.se>
Subject: Re: I made a patch and would like feedback/testers (drivers/cdrom/aztcd.c)
Date: Mon, 21 Nov 2005 20:11:47 +1100
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On Mon, 21 Nov 2005 19:42, Daniel Marjam?ki wrote:
> Con Kolivas wrote:
> > Convention in the kernel would be
> > 	aztTimeOut =  HZ / 100 ? : 1;
> > to be at least one tick (works for HZ even below 100) and is at least
> > 10ms. If you wanted 2 ms then use
> > 	aztTimeOut =  HZ / 500 ? : 1;
> > which would give you at least 2ms
>
> Thank you Con for the feedback.
>
> Hmm.. The minimum value should be 2, right?
> Otherwise the loop could time out after only a few nanoseconds.. since the
> loop will then timeout immediately on a clock tick. Or am I wrong?

 	aztTimeOut =  HZ / 500 ? : 1;
Would give you a 2ms timeout on 1000Hz and 500Hz
It would give you 5ms on 250Hz and 10ms on 100Hz

ie the absolute minimum it would be would be 2ms, but it would always be at 
least one timer tick which is longer than 2ms at low HZ values.

Cheers,
Con
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