From owner-freebsd-arch Tue Nov 21 19:15:53 2000 Delivered-To: freebsd-arch@freebsd.org Received: from pcnet1.pcnet.com (pcnet1.pcnet.com [204.213.232.3]) by hub.freebsd.org (Postfix) with ESMTP id AF09137B479; Tue, 21 Nov 2000 19:15:50 -0800 (PST) Received: (from eischen@localhost) by pcnet1.pcnet.com (8.8.7/PCNet) id WAA27327; Tue, 21 Nov 2000 22:15:28 -0500 (EST) Date: Tue, 21 Nov 2000 22:15:28 -0500 (EST) From: Daniel Eischen To: Alfred Perlstein Cc: John Baldwin , Jonathan Lemon , arch@FreeBSD.ORG Subject: Re: Thread-specific data and KSEs In-Reply-To: <20001121175100.B18037@fw.wintelcom.net> 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 Tue, 21 Nov 2000, Alfred Perlstein wrote: > * John Baldwin [001121 17:19] wrote: > > > > On 22-Nov-00 Daniel Eischen wrote: > > >> %gs ? as I mentioned in my other message, this one might be useful for > > >> addressing a structure of thread-local variables much like %fs is used for > > >> per-CPU data. It also has value in that supposedly x86-64 (aka k64) has > > >> both > > >> %fs and %gs, but no other seg regs. > > > > > > All I need is one. > > > > Well, %gs would cover x86 and k64. I think ia64 has several application > > registers that are available for OS use and we could steal one of those. I'm > > not sure about the alpha though. > > Don't more segment registers cause more overhead for context switches? It's just one more register that has to be saved. I don't think it's going to matter much. -- "Some folks are into open source, but me, I'm into open bar." -- Spencer F. Katt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message