From owner-freebsd-current@FreeBSD.ORG Sun Jul 30 12:23:48 2006 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8917E16A4DA for ; Sun, 30 Jul 2006 12:23:48 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1970C43D45 for ; Sun, 30 Jul 2006 12:23:48 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from localhost (localhost [127.0.0.1]) by pi.codefab.com (Postfix) with ESMTP id 917DF5DAC; Sun, 30 Jul 2006 08:23:47 -0400 (EDT) X-Virus-Scanned: amavisd-new at codefab.com Received: from pi.codefab.com ([127.0.0.1]) by localhost (pi.codefab.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 1ssIzrfqXHjI; Sun, 30 Jul 2006 08:23:46 -0400 (EDT) Received: from [192.168.1.251] (pool-68-161-117-245.ny325.east.verizon.net [68.161.117.245]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by pi.codefab.com (Postfix) with ESMTP id 3B1505C33; Sun, 30 Jul 2006 08:23:46 -0400 (EDT) Message-ID: <44CCA4CD.1050309@mac.com> Date: Sun, 30 Jul 2006 08:23:41 -0400 From: Chuck Swiger User-Agent: Thunderbird 1.5.0.5 (Windows/20060719) MIME-Version: 1.0 To: Peter Jeremy References: <20060728210154.GC748@turion.vk2pj.dyndns.org> <1154189612.1565.10.camel@genius.i.cz> <20060729205655.GE748@turion.vk2pj.dyndns.org> <20060729211530.GA50342@uk.tiscali.com> <1154212340.3609.18.camel@genius.i.cz> <20060729230214.GI12597@groat.ugcs.caltech.edu> <1154216319.23616.23.camel@genius.i.cz> <1154217036.23616.28.camel@genius.i.cz> <20060730005342.GJ12597@groat.ugcs.caltech.edu> <1154250451.23616.37.camel@genius.i.cz> <20060730115427.GD1310@turion.vk2pj.dyndns.org> In-Reply-To: <20060730115427.GD1310@turion.vk2pj.dyndns.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-current@freebsd.org Subject: Re: vmstat's entries type X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 30 Jul 2006 12:23:48 -0000 Peter Jeremy wrote: [ ... ] > This was based on an examination of /usr/src/sys/*/include/atomic.h. > It looks like I was overly quick because the RISC architectures are > using compare-and-swap, rather than test-and-set primitives - sorry > about the error. The details are: [ ... ] > - ppc doesn't support 64-bit atomic operations lwarx/stwcx...? http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/aixassem/alangref/lwarx.htm http://www-128.ibm.com/developerworks/library/pa-atom/ > - sparc64 uses cas in a loop. > > Whilst true spinlocks are not needed, amd64 is the only architecture > FreeBSD supports that does not require some sort of loop to perform > a 64-bit atomic operation. You can use membar instructions on the SPARCv9 to enforce various memory models (RMO, PSO, TSO, if not full sequential consistency). -- -Chuck