From owner-freebsd-current Mon Sep 22 13:37:39 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id NAA17684 for current-outgoing; Mon, 22 Sep 1997 13:37:39 -0700 (PDT) Received: from pluto.plutotech.com (root@mail.plutotech.com [206.168.67.137]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id NAA17679 for ; Mon, 22 Sep 1997 13:37:37 -0700 (PDT) Received: from narnia.plutotech.com (narnia.plutotech.com [206.168.67.130]) by pluto.plutotech.com (8.8.5/8.8.5) with ESMTP id OAA01057; Mon, 22 Sep 1997 14:37:21 -0600 (MDT) Message-Id: <199709222037.OAA01057@pluto.plutotech.com> X-Mailer: exmh version 2.0zeta 7/24/97 To: Nate Williams cc: "Justin T. Gibbs" , Bruce Evans , current@FreeBSD.ORG Subject: Re: cvs commit: src/sys/conf files src/sys/dev/vx if_vx.c if_vxreg.h src/sys/i386/apm apm.c src/sys/i386/conf GENERIC files.i386 src/sys/i386/eisa 3c5x9.c aha1742.c aic7770.c bt74x.c eisaconf.c eisaconf.h if_fea.c if_vx_eisa.c src/sys/i386/i386 autoconf.c ... In-reply-to: Your message of "Mon, 22 Sep 1997 13:07:22 MDT." <199709221907.NAA02110@rocky.mt.sri.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 22 Sep 1997 14:37:10 -0600 From: "Justin T. Gibbs" Sender: owner-freebsd-current@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk >> The current implementation only needs to allocate a callout at a time if >> it wants to grow the number of callouts. It may, in fact be nice to add >> an interface for clients to add additional callouts if they are heavy >> users of them. For instance, the CAM system grows it's number of >> transactions dynamically and will simply stop growing if it can't malloc >> more. In your scenario, if you can't allocate space for a drive and it's >> transactions, you can't talk to the drive. > >Umm, how does the CAM system still talk to a drive if it can't establish >a callout for it? If it can do that now, then it can certainly do it >with the old solution. I assume that I can allocate a single CCB/callout at boot time. If this is the case, I can talk to any number of devices by serializing the transactions. It won't be fast, but it won't fail either. CCB = CAM Control Block - a structure used to encapsulate a CAM transaction. >Nate -- Justin T. Gibbs =========================================== FreeBSD: Turning PCs into workstations ===========================================