Randell Jesup wrote...
>       This discussion should probably move to the freebsd-scsi list...
> 
> "Kenneth D. Merry" <[EMAIL PROTECTED]> writes:
> >Nick Hibma wrote...
> >> Especially some help on the topic of polling would be appreciated.
> >> Otherwise I'll have to resort to figuring out how to do things in
> >> interrupt context, and that is going to be dirty.
> 
> >If you're talking about polling for transaction completion in a device
> >driver, my guess is that you're going to have to do things in an interrupt
> >context.  (Unless you use a kernel process to do it.)
> >
> >The thing to remember is that when you get CCBs down in a CAM device
> >driver, it may well be in an interrupt context.  You have to be able to
> >deal with that.  My guess is that it might be easiest to just use a timeout
> >handler to poll the device for completion every so often.  A kernel process
> >may also be an option, depending on how nasty the device is.
> 
>       Ick.  Polling == bad.  Interrupts == good.  This isn't a single-
> tasking OS ala Win9x.  This goes double for SCSI drivers, which are
> inherently async and overlapped.

I never said polling was good.  Nick just asked about polling, and I
commented on how it could be done.  I have no idea why he wanted to know
about polling, though.

Ken
-- 
Kenneth Merry
[EMAIL PROTECTED]


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