Subject: Re: fast timeouts (< 1 millisecond)??
To: Matt Thomas <matt@lkg.dec.com>
From: Chris G Demetriou <Chris_G_Demetriou@ux2.sp.cs.cmu.edu>
List: tech-kern
Date: 11/14/1996 16:00:58
> It would really be helpful to my driver if there was a mechanism to 
> schedule quick timeouts (ie. much less than 1/hz and usually on the
> order of 10s of microseconds)?
> 
> Currently, some of my driver spin for 1 millisecond (or less) and
> I'd like to see the system do something other than reading a CSR
> for that time.
> 
> Any comments?

Well, i suppose i've got a couple of questions, like:

	(1) what would you have the system doing?

	(2) what method would you suggest for having the system figure
	    out when to stop delaying?

On many ports, it's hard to get finer-granularity timing than 'hz' to
begin with...

While it is annoying to have to spin loop in drivers and waste cycles,
i'd like to know what the alternatives could be...


chris