From owner-freebsd-smp Wed Aug 22 23:38:53 2001 Delivered-To: freebsd-smp@freebsd.org Received: from falcon.mail.pas.earthlink.net (falcon.mail.pas.earthlink.net [207.217.120.74]) by hub.freebsd.org (Postfix) with ESMTP id 1791E37B40C; Wed, 22 Aug 2001 23:38:48 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from mindspring.com (dialup-209.245.134.55.Dial1.SanJose1.Level3.net [209.245.134.55]) by falcon.mail.pas.earthlink.net (EL-8_9_3_3/8.9.3) with ESMTP id XAA15482; Wed, 22 Aug 2001 23:38:40 -0700 (PDT) Message-ID: <3B84A51A.3BC5689F@mindspring.com> Date: Wed, 22 Aug 2001 23:39:22 -0700 From: Terry Lambert Reply-To: tlambert2@mindspring.com X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Matt Dillon Cc: Bruce Evans , Jake Burkholder , John Baldwin , freebsd-smp@FreeBSD.ORG, freebsd-alpha@FreeBSD.ORG Subject: Re: Preliminary proposed rollup of kernel submap initialization code References: <20010823060618.M15348-100000@besplex.bde.org> <200108222039.f7MKdeW78135@earth.backplane.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Matt Dillon wrote: > Look, I don't want to get into a big argument. It makes sense to > keep them together because they are related, and even though our > existing platforms do not appear to need them I can see that changing > in the future as we add more platform ports to the system. For example, > having the pager range accessible could be advantageous for platforms > that take TLB faults. For a MIPS or other processors where TLBs are done in software, using the pointer could get vastly more expensive than a global reference, if you had to look in there for every shootdown, and an LRU shootdown of at least one entry happened on nearly every context switch. As for keeping them together, I understand the desire to have them around for doing automatic limits calculations, but if that's going to happen, it should be that they are required to be initialized past a certain point on all platforms, or they are MD, and don't belong in an MI structure. I agree that they are related -- just that they are related by machine dependencies on a platform which isn't supported yet (I don't think we need to worry about Chris D. switching the Sibytes card away from NetBSD any time soon, for example 8-)). -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message