From owner-svn-src-all@FreeBSD.ORG Wed Oct 31 23:25:56 2012 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id EEEC337E; Wed, 31 Oct 2012 23:25:55 +0000 (UTC) (envelope-from jim.harris@gmail.com) Received: from mail-qc0-f182.google.com (mail-qc0-f182.google.com [209.85.216.182]) by mx1.freebsd.org (Postfix) with ESMTP id 3E36D8FC12; Wed, 31 Oct 2012 23:25:54 +0000 (UTC) Received: by mail-qc0-f182.google.com with SMTP id k19so1723424qcs.13 for ; Wed, 31 Oct 2012 16:25:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=tvEuR6/64EyPVl0CJfheNwt1Bxt0nSTCAUvvLHuGuug=; b=KrfGnz4qy6hElSI8miC+yOOxs2eJghqCJbG6sErrPFU/71uswoHFgm9rtaXSRmpBwM BvaJ5RqE7wY2wqmwF7UmZmOT2CmJKl3GNhIxF/lhHTocQ4WF8c26ev96WPG2NnXkc6Zl L3uTYFVRrC34T/JluHiCY2McpK1XrTztsK/4sd/AnT11iCbum+fB9GMn11ZicQVHgFyY 3R69ouFfSuuxCgAyla/iDU/D+lN3PuFJEivwfWN1Wyqhq1kloDiCXAxx0ugIIBa1Nq1+ vxQriH9+7i1kr/O3h4xzbxyoJ8UaxwUKQ62RQqLTfO4slZnKyDNsSCBXgN7z/tRFT6fH 92Yw== MIME-Version: 1.0 Received: by 10.224.42.8 with SMTP id q8mr25453044qae.77.1351725954520; Wed, 31 Oct 2012 16:25:54 -0700 (PDT) Received: by 10.49.35.37 with HTTP; Wed, 31 Oct 2012 16:25:54 -0700 (PDT) In-Reply-To: References: <201210311807.q9VI7IcX000993@svn.freebsd.org> <1351707964.1120.97.camel@revolution.hippie.lan> <20121031193020.GJ3309@server.rulingia.com> <1351712425.1120.109.camel@revolution.hippie.lan> <50918AAD.2090906@freebsd.org> Date: Wed, 31 Oct 2012 16:25:54 -0700 Message-ID: Subject: Re: svn commit: r242402 - in head/sys: kern vm From: Jim Harris To: attilio@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: Ian Lepore , Adrian Chadd , src-committers@freebsd.org, Andre Oppermann , svn-src-all@freebsd.org, svn-src-head@freebsd.org, Peter Jeremy X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 31 Oct 2012 23:25:56 -0000 On Wed, Oct 31, 2012 at 3:55 PM, Attilio Rao wrote: > On Wed, Oct 31, 2012 at 8:31 PM, Andre Oppermann > wrote: > > You can define CACHE_LINE_SIZE to 0 on those platforms. > > Or to make it even more granular there could be a CACHE_LINE_SIZE_LOCKS > > that is used for lock padding. > > I think that this is a bright idea, albeit under the condition that > just like CACHE_LINE_SIZE it won't change during STABLE branches > timeframe and that it must not be dependent by SMP option. > > What do you think about this patch?: > http://www.freebsd.org/~attilio/cache_line_size_locks.patch > Should CACHE_LINE_SIZE_LOCKS still be defined as CACHE_LINE_SIZE on arm, mips, etc. if SMP is enabled? This would ensure the padding that used to be there in vpglock doesn't go away. I'm also wondering if this should be named something different, perhaps LOCK_ALIGNMENT. -Jim