From owner-freebsd-current Fri Jan 31 12:43:10 2003 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 57ED837B401; Fri, 31 Jan 2003 12:43:09 -0800 (PST) Received: from rwcrmhc51.attbi.com (rwcrmhc51.attbi.com [204.127.198.38]) by mx1.FreeBSD.org (Postfix) with ESMTP id E7E9E43FC7; Fri, 31 Jan 2003 12:43:08 -0800 (PST) (envelope-from julian@elischer.org) Received: from InterJet.elischer.org (12-232-168-4.client.attbi.com[12.232.168.4]) by rwcrmhc51.attbi.com (rwcrmhc51) with ESMTP id <2003013120430505100hvc9se>; Fri, 31 Jan 2003 20:43:05 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id MAA46568; Fri, 31 Jan 2003 12:43:04 -0800 (PST) Date: Fri, 31 Jan 2003 12:43:03 -0800 (PST) From: Julian Elischer To: John Baldwin Cc: "Daniel C. Sobral" , freebsd-current@FreeBSD.ORG, Trish Lynch , Matthew Dillon Subject: Re: Hyperthreading and machdep.cpu_idle_hlt In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Fri, 31 Jan 2003, John Baldwin wrote: > >> AT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,,ACC> > >> > >> It has HTT set but it's only a 1.2GHz box and I heard somewhere that only > >> 2+ GHz P4's had hyperthreading. I noticed some MFCs to stable that > >> suggested hyperthreading support but I do not know if full hyperthreading > >> support has been MFCd yet or is intended to be MFCd to -stable. > > > > AFAIK, full hyperthreading support, as it is, has been merged to > > -stable. It consists of a patch to recognize the virtual CPUs, so they > > will be dealt with like any SMP system, as long as HTT is enabled on the > > BIOS. > > Well, sort of. We have no way of knowing if it is off in the BIOS unless > we use the ACPI tables to enumerate CPU's (which we don't), so turning it > off in the BIOS won't turn it off in FreeBSD for the time being. :) > I have a 2,8GHz p4 here which has HTT and has a bios option for Interrupt mode: [APIC/PIC] I'm using APIC mode but an SMP (today's 4.x) kernel panics imediatly saying it can;t find an APIC. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message