From owner-freebsd-arch Thu May 25 11:49:48 2000 Delivered-To: freebsd-arch@freebsd.org Received: from rover.village.org (rover.village.org [204.144.255.49]) by hub.freebsd.org (Postfix) with ESMTP id 935A137B6DC for ; Thu, 25 May 2000 11:49:44 -0700 (PDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (harmony.village.org [10.0.0.6]) by rover.village.org (8.9.3/8.9.3) with ESMTP id MAA20004; Thu, 25 May 2000 12:49:43 -0600 (MDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (localhost.village.org [127.0.0.1]) by harmony.village.org (8.9.3/8.8.3) with ESMTP id MAA85904; Thu, 25 May 2000 12:48:33 -0600 (MDT) Message-Id: <200005251848.MAA85904@harmony.village.org> To: Peter Wemm Subject: Re: Preemptive kernel on older X86 hardware Cc: arch@FreeBSD.ORG In-reply-to: Your message of "Thu, 25 May 2000 11:37:13 PDT." <20000525183713.B28F31CE1@overcee.netplex.com.au> References: <20000525183713.B28F31CE1@overcee.netplex.com.au> Date: Thu, 25 May 2000 12:48:33 -0600 From: Warner Losh Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message <20000525183713.B28F31CE1@overcee.netplex.com.au> Peter Wemm writes: : Digital Unix (Tru64) does this too according to their white papers. : Everything is compiled to use the generic lock calls. The generic routine : modifies the caller binary code to instead call the specific routines for : the cpu configuration or replaces the call with NOPs for uniprocessor : systems. IRIX (and now Linux/mips) will bcopy the right interrupt routine to the fixed location in memory where these things live on the MIPS cpu based on what CPU you have, even to the point of having specific versions with work arounds for specific revs of the CPU (eg a R44000 v 2.2 will get the routine that works around bugs in that chip, while a R4400 v5.0 will get a faster version since that chip has no know bugs and a R3000A will get a completely different routine, etc). Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message