From owner-freebsd-arch@FreeBSD.ORG  Tue Jul 25 15:13:14 2006
Return-Path: <owner-freebsd-arch@FreeBSD.ORG>
X-Original-To: freebsd-arch@freebsd.org
Delivered-To: freebsd-arch@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 674BE16A51C
	for <freebsd-arch@freebsd.org>; Tue, 25 Jul 2006 15:13:14 +0000 (UTC)
	(envelope-from asmrookie@gmail.com)
Received: from wx-out-0102.google.com (wx-out-0102.google.com [66.249.82.199])
	by mx1.FreeBSD.org (Postfix) with ESMTP id AEA6343D45
	for <freebsd-arch@freebsd.org>; Tue, 25 Jul 2006 15:13:13 +0000 (GMT)
	(envelope-from asmrookie@gmail.com)
Received: by wx-out-0102.google.com with SMTP id i31so976848wxd
	for <freebsd-arch@freebsd.org>; Tue, 25 Jul 2006 08:13:13 -0700 (PDT)
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com;
	h=received:message-id:date:from:sender:to:subject:cc:mime-version:content-type:content-transfer-encoding:content-disposition:x-google-sender-auth;
	b=P2EVHfsFDdJWzxFj9Zec/KTAwcbyaqtlAIzVPyTxvF4S5lSFBnRxm8gE0ltxne5zGMMQ272qRVSX8+58VGbxPO96jGKbQSpmwjA+71cD0y/8Qnj238gG+c1LxfrzWsnnyzAxdD5xFPiV5dJa2KrgWizWJuLlqGeu6/Ey7RyEdBw=
Received: by 10.70.44.5 with SMTP id r5mr820589wxr;
	Tue, 25 Jul 2006 08:13:12 -0700 (PDT)
Received: by 10.70.11.18 with HTTP; Tue, 25 Jul 2006 08:13:12 -0700 (PDT)
Message-ID: <3bbf2fe10607250813w8ff9e34pc505bf290e71758@mail.gmail.com>
Date: Tue, 25 Jul 2006 17:13:12 +0200
From: "Attilio Rao" <attilio@freebsd.org>
Sender: asmrookie@gmail.com
To: freebsd-arch@freebsd.org
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
X-Google-Sender-Auth: cc91b2f89e4d364c
Cc: 
Subject: [PATCH] Mantaining turnstile aligned to 128 bytes in i386 CPUs
X-BeenThere: freebsd-arch@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussion related to FreeBSD architecture <freebsd-arch.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>,
	<mailto:freebsd-arch-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-arch>
List-Post: <mailto:freebsd-arch@freebsd.org>
List-Help: <mailto:freebsd-arch-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>,
	<mailto:freebsd-arch-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 25 Jul 2006 15:13:14 -0000

Hi,
Intel documentation points out that having a 128-bytes aligned
syncronizing primitive  (which fits in a cache line) will minimize the
traffic for cache bus, so this patch implements an alignment for i386
on turnstiles.

Any comments, feedbacks?

Attilio

PS: Using __aligned on MI code is usually a bad practice, but please
note that the case !__i386__ is not affected (as you can see in the
patch)


-- 
Peace can only be achieved by understanding - A. Einstein