From owner-freebsd-hackers Tue Jan 20 18:38:53 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id SAA02289 for hackers-outgoing; Tue, 20 Jan 1998 18:38:53 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from smtp04.primenet.com (smtp04.primenet.com [206.165.6.134]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id SAA02245 for ; Tue, 20 Jan 1998 18:38:33 -0800 (PST) (envelope-from tlambert@usr08.primenet.com) Received: (from daemon@localhost) by smtp04.primenet.com (8.8.8/8.8.8) id TAA16064; Tue, 20 Jan 1998 19:38:30 -0700 (MST) Received: from usr08.primenet.com(206.165.6.208) via SMTP by smtp04.primenet.com, id smtpd016051; Tue Jan 20 19:38:22 1998 Received: (from tlambert@localhost) by usr08.primenet.com (8.8.5/8.8.5) id TAA01077; Tue, 20 Jan 1998 19:38:20 -0700 (MST) From: Terry Lambert Message-Id: <199801210238.TAA01077@usr08.primenet.com> Subject: Re: fastintr interrupt handler To: weeteck@eecs.umich.edu (Wee Teck Ng) Date: Wed, 21 Jan 1998 02:38:20 +0000 (GMT) Cc: freebsd-hackers@FreeBSD.ORG In-Reply-To: <199801202248.RAA27603@singapore.eecs.umich.edu> from "Wee Teck Ng" at Jan 20, 98 05:48:47 pm X-Mailer: ELM [version 2.4 PL25] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk > i've a question concerning the two different types of interrupt > handler: fastintr and slowintr. i've looked at the code in vector.s, > and somewhat understands what both do. i've also gathered from sio.c > that comm port 1 & 2 uses fastintr. my question is: > > - is it safe to use fastintr for keyboard? For input, probably; for LED changes... ugh. It would mean you'd need status so that the fastintr/slow stuff didn't interfere with each other. I think, though, that Bruce would hate using it for keyboards. It's really for stuff with small buffers that has to run to completion in the interrupt routine (and that's a watered down version of a very long explanation that Bruce posted a while back). The one thing I can think of that I might throw in there would be a floppy tape driver, and that would be hideous. 8-|. You can also ask Bruce directly (hopefully on the list so I can save what he says about it). Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.