Subject: Re: have scsibus sleep only one time
To: Bill Studenmund <wrstuden@netbsd.org>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: tech-kern
Date: 03/10/2003 02:44:00
On Sun, Mar 09, 2003 at 04:10:22PM -0800, Bill Studenmund wrote:
> On Sun, 9 Mar 2003, Manuel Bouyer wrote:
> 
> > Hi,
> > would anyone object to the attached change ?
> > It makes all the attached scsibusses sleep "in parallel" instead of
> > sequencially, which is a real win for machines with several SCSI busses.
> > On my DS20, which has 8 scsi busses, this saves 14 seconds on boot.
> 
> I'll be honest, I don't know that part of the code well. I assume that the
> resetting of all busses occured above where you moved the code to?
> 
> i.e. we reset all busses, sleep once, then probe all busses? One question,

Yes, the reset happens at HBA attach time.

> won't that make the per-bus check, (chan->chan_flags &
> SCSIPI_CHAN_NOSETTLE) == 0, useless?

No, this flag is used by hot-plug busses (e.g. scsi over USB).

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 24 ans d'experience feront toujours la difference
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