From owner-freebsd-arch Wed May 24 8:32:31 2000 Delivered-To: freebsd-arch@freebsd.org Received: from haldjas.folklore.ee (Haldjas.folklore.ee [193.40.6.121]) by hub.freebsd.org (Postfix) with ESMTP id 63E8137BCC3 for ; Wed, 24 May 2000 08:32:23 -0700 (PDT) (envelope-from narvi@haldjas.folklore.ee) Received: from localhost (narvi@localhost) by haldjas.folklore.ee (8.9.3/8.9.3) with SMTP id RAA33569; Wed, 24 May 2000 17:30:35 +0200 (EET) (envelope-from narvi@haldjas.folklore.ee) Date: Wed, 24 May 2000 17:30:35 +0200 (EET) From: Narvi To: Kazutaka YOKOTA Cc: Chuck Paterson , arch@FreeBSD.ORG Subject: Re: Preemptive kernel on older X86 hardware In-Reply-To: <200005241519.AAA20525@zodiac.mech.utsunomiya-u.ac.jp> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thu, 25 May 2000, Kazutaka YOKOTA wrote: > [...] > >Neither the 386 nor the 486 have a processor priority register or > >cycle counters. Currently the BSD/OS SMPng kernel requires both of > >these. There already exists some left over code to deal with not > >having a cycle counter. Doing a casual inspection there really > >doesn't seem to be anything too ugly in making the system run > >without these when there is only a single processor. > > 386 and 486 do not support multi-processor configuration, don't they? > They do in principle, but the fact can be overlooked. But loosing the ability to run on x86, x<5 is catastrophic. > Kazu > Sander sander@haldjas.folklore.ee To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message