From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263024AbUEHOLv (ORCPT ); Sat, 8 May 2004 10:11:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262217AbUEHOLv (ORCPT ); Sat, 8 May 2004 10:11:51 -0400 Received: from pxy7allmi.all.mi.charter.com ([24.247.15.58]:41369 "EHLO proxy7-grandhaven.chartermi.net") by vger.kernel.org with ESMTP id S262914AbUEHOLu (ORCPT ); Sat, 8 May 2004 10:11:50 -0400 Message-ID: <409CEB4B.3070909@quark.didntduck.org> Date: Sat, 08 May 2004 10:14:35 -0400 From: Brian Gerst User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040506 X-Accept-Language: en-us, en MIME-Version: 1.0 To: read lkml CC: linux-kernel@vger.kernel.org Subject: Re: Question regarding switch_to on x86 References: <20040507194448.24330.qmail@web90006.mail.scd.yahoo.com> In-Reply-To: <20040507194448.24330.qmail@web90006.mail.scd.yahoo.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Charter-MailScanner-Information: X-Charter-MailScanner: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org read lkml wrote: > Hi, > > Could anyone please explain to me (or point me to some > documentation) the need for the 3rd argument in the > switch_to macro on x86? Why is it > switch_to(prev, next, last)? how are prev and last > different? > > Thanks > last is actually a return value. Since switch_to() switches stacks, last must be passed through in a register. -- Brian Gerst