Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263441AbUJ2SDS (ORCPT ); Fri, 29 Oct 2004 14:03:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263429AbUJ2R7U (ORCPT ); Fri, 29 Oct 2004 13:59:20 -0400 Received: from mx1.redhat.com ([66.187.233.31]:20412 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S263382AbUJ2Rzo (ORCPT ); Fri, 29 Oct 2004 13:55:44 -0400 Date: Fri, 29 Oct 2004 10:55:27 -0700 From: Richard Henderson To: linux-os@analogic.com Cc: Linus Torvalds , Kernel Mailing List , Andi Kleen , Andrew Morton , Jan Hubicka Subject: Re: Semaphore assembly-code bug Message-ID: <20041029175527.GB25764@redhat.com> References: <417550FB.8020404@drdos.com> <1098218286.8675.82.camel@mentorng.gurulabs.com> <41757478.4090402@drdos.com> <20041020034524.GD10638@michonline.com> <1098245904.23628.84.camel@krustophenia.net> <1098247307.23628.91.camel@krustophenia.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 816 Lines: 22 On Fri, Oct 29, 2004 at 01:22:52PM -0400, linux-os wrote: > Here's a version that uses `leal 4(esp), esp` to add > 4 to the stack-pointer. Since this 'address-calculation` > is done in an different portion of Intel CPUs.... Incorrect, at least i686 and beyond. These interpret to the same micro-ops. > The 'pop ecx' would access memory and, therefore be slower than > simple register operations. Also not necessarily correct. Intel cpus special-case pop instructions; two pops can be dual issued, whereas a different kind of stack pointer manipulation will not. r~ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/